There is, however, less tendency to infection with the microbes forming pus. There is a greater tendency to deteriorating action on the nervous system. There is in chronic alcoholism, as in syphilis, special tendency to that formation of connective tissue which destroys organs. The chronic mental disorders of chronic alcoholism resemble those of tuberculosis except that the capricious state and exaltation are less frequent than the suspicional tendency which is deeper, and takes the direction of delusions of poisoning and insane jealousy. The last are due to the deteriorating influence of alcohol on the generative organs. Alcohol may limit its action to the central nervous system, and thus produce hereditary losses of power. It causes changes in the peripheral nerves which in the offspring find expression in spinal cord and brain disorder through extension of the morbid process. But for its deteriorating effects on the ovaries and t.e.s.t.i.c.l.es, alcohol would be a most serious social danger.

Through its action on the generative organs it tends to prevent the survival of the unfit, rather than to develop degenerates.

Opium seems to be the Charybdis on which the human bark strikes when escaping from the Scylla of alcohol. Its abuse as a narcotic is much older, even among the English-speaking races, than is generally suspected.

Murrell, over ten years ago, demonstrated that the inhabitants of the fens of Lincolnshire had long employed opium as a prophylactic against malaria.

The ratio of insanity in these regions proved to be very great. The same conditions obtained in certain malarial regions of New Jersey and Pennsylvania, where the use of strong infusions of poppy was common. The statistics of Rush[154] as to opium-caused insanity in Pennsylvania, indicate that the percentage of American opium abuses at the beginning of the nineteenth century was very great. The drug differs in two serious respects from alcohol. It is nearer in chemical composition to nerve tissue, and the tendency to its use may be transmitted by the mother directly to the foetus. This, as Bureau and Ringer have shown, receives through the placenta from its opium-using mother a certain amount of morphine. In consequence, the child in the first month of infancy must be nourished on the milk of an opium-using woman, or given opium in some other way lest it perish. To this fact Calkins[155] was the first to call attention. His results were corroborated later by Hubbard; Kiernan, of Chicago[156]; Erlenmeyer, of Berlin; F. B. Earle, of Chicago; Mattison, of Brooklyn; Hughes, of St. Louis; and others. Amabile, of New York, showed that not only were the children of opium-using mothers born with tendency to the opium habit, but that the mothers aborted frequently with twins, and that the children who survived were very liable to convulsions.

Independently of this factor the mental state produced by opium habit resembles in many respects that of the lunatic, in that the victim of opium is as unable to distinguish between his wishes and the facts, and therefore often utters what appear to be sheer lies. Hence he is totally unreliable and has taken a step in mental and moral degeneracy that, by the ordinary laws of heredity, must greatly increase, unless corrected by healthy atavism and training in the next generation. Opium is a more dangerous factor of degeneracy than alcohol, since the opium user must be in a continuous state of intoxication to carry on his usual avocation, while abstinence is perfectly compatible with proper work on the part of the drunkard. The opium habit is increased by the peculiar propaganda carried on by the _habitues_ who justify their position by urging the use of opium for any ailment, however minimal. Opium, like alcohol, causes nervous exhaustion similar to, but greater than, that of the contagions and infections. From the affinity of opium to nerve tissue, from its tendency to stimulate the heart, thus causing increased blood supply to the brain; from its action on the bowels and the increased resultant work of the liver, this nervous state is much intensified. Opium does not have as great tendencies to interfere with the structure of the ovary and t.e.s.t.i.c.l.es as alcohol, hence the greater danger of the opium _habitue's_ children surviving. Opium, when smoked, stimulates the reproductive apparatus, and thus would greatly increase the number of degenerates due to this habit but for the defects due to the inheritance of the habit and their consequences.

[Ill.u.s.tration: FIG. 1.--ANTE-CHRISTIAN IRISH PIPES.]

[Ill.u.s.tration: FIG. 2.--ANTE-COLUMBIAN PIPES FROM SCULPTURE AT STRATFORD-UPON-AVON.]

The origin of the use of tobacco is usually ascribed to the New World.

There is no doubt that immediately subsequent to the discovery of America, the use of tobacco spread over the world, and that its employment by Sir Walter Raleigh made it fashionable. It is certain, however, that the Romans and Irish employed pipes for smoking long ere the Christian era (Fig. 1), but the substances smoked were not tobacco but dried aromatic leaves. The English before Columbus (Fig. 2) did the same. In Western Asia historic botanical evidence leaves no doubt that tobacco was indigenous.

Tobacco from the East hence probably encountered tobacco from the West, both currents meeting in Asia Minor. As with alcohol and opium the statistic method generally adopted proves fallacious when applied to the degenerative effects of tobacco. Study of its effects on the individual is needed to determine its effects on the race. The most careful researches show that the typical effects occur as a rule after long-continued use of tobacco, sometimes not until twenty years or more. While many smokers reach old age, many fail to live to old age because they are smokers. The skin is the subject of itching and reddening, the nerves of taste are blunted, and patches develop in the throat; loss of appet.i.te, epigastric fulness, pain, vomiting, and disturbance of bowel function are common.

Menstrual disturbance occurs in women. In female cigar-makers abortion and pluriparity are frequent. The s.e.xual appet.i.te is impaired and sometimes sterility and impotence occur; also disturbed heart action, palpitation, rapid and intermitting pulse, precordial anxiety, weakness, faintness and collapse, with sclerosis of the coronary arteries of the heart and left ventricular hypertrophy. Cigars and cigarettes produce irritation of the nose, mucous membrane, diminished smell, chronic hyperaemia of the epiglottis and larynx, and sometimes of the trachea and bronchi predisposing to consumption. Nicotine amblyopia, or sight weakness, is common, with central disturbances of the field of vision and with colour-weakness of sight. Often there is disorder of the ear tubes and congestion of drum, with loss of power of the hearing nerves, and consequent noises in the ear. The central nervous system is affected. In high schools, non-smokers get on better than smokers. Children from 9 to 15 years of age exhibit less intelligence, laziness, or other degenerative tendencies. Adults have head-pressure, sleeplessness, or drowsy stupor, depression, apathy, and dizziness. There may also be ataxic symptoms, paretic weakness of bowel and bladder, trembling and spasms. Tobacco insanities are comparatively rare in smokers, but are common in snuffers and still oftener in chewers.[157] In the precursory stage, which lasts about three months, there is general uneasiness, restlessness, anxiety, sleeplessness, and mental depression, often of a religious type. After this occurs precordial anxiety, and finally the psychosis proper consisting of three stages: 1. Hallucinations of all senses, suicidal tendency, depression of spirits, attacks of fright with tendency to violence and sleeplessness. 2. Exhilaration, slight emotional exaltation, agreeable hallucinations after from two to four weeks' relaxation, again followed by excitement. 3. The intervals between exaltation and depression diminish, the patient becomes irritable, but otherwise not alive to his surroundings, and perception and attention are lessened. The patient may be cured in five or six months if he stop tobacco during the first stage.

In a year or so he may recover during the second stage. After the third stage the disease is frequently incurable. As the patient often becomes (especially by the use of the cigarette) an _habitue_ ere p.u.b.erty, the proper development and balance of the s.e.xual and intellectual system is checked. These patients break down mentally and physically between 14 and 25. The moral delinquencies, other than s.e.xual, are often an especial tendency to forgery and deceit of parents. Frequently the insanity of p.u.b.erty (hebephrenia) is precipitated by tobacco. The cigarette, if used moderately, may be a sedative, but as used is a stimulant, and is often made of spoiled tobacco, resembling in reaction morphine, and on animals acting in a somewhat similar manner. As tobacco turns the salivary glands (which are concerned in digestion of starch) into excretory glands, it leads to imperfect digestion of starch, to consequent irregular fermentation in the bowel, thus at once furnishing a culture medium for microbes, to form more violent toxins from, and also creating leucomaines, to interfere especially with a nervous system overstimulated by nicotine.

This is one great reason why those who snuff and chew tobacco more frequently become insane from tobacco than smokers, albeit these last are not exempt.

Statistics from the female employes of the Spanish, French, Cuban, and American tobacco factories, while defective and somewhat vitiated by the co-existence of other conditions producing degeneracy, support the opinion that the maternal tobacco habit (whether intentional or the result of an atmosphere consequent on occupation) is the cause of frequent miscarriage, of high infantile mortality, of defective children, and of infantile convulsions.[158]

Tobacco, therefore, in its influence on the paternal and maternal organism, exhausts the nervous system so that an acquired neurosis results in such a way as to be transmissible.

Professional tea-tasters have long been known to suffer from nervous symptoms; very early in the practice of their occupation the head pressure symptoms of neurasthenia occur. Tremor also occurs early. While changes in the optic nerve have not been demonstrated beyond a doubt, still eye disorders have been observed in the pauper tea-drinkers of the United States and in the tea-tasters of Russia, thus indicating that similar changes to those produced by tobacco and alcohol are likely to occur in the optic nerve from tea. Bullard[159] has found that tea has a c.u.mulative effect. In his experience toxic effects are not produced by less than five cups daily. The symptoms manifested are those of nervous excitement resembling hysteria, at times almost amounting to fury; nervous dyspepsia; rapid and irregular heart action; neuralgia of the heart; helmet-like sensation on the head, and tenderness along the spine. James Wood,[160] of Brooklyn, found that 10 per cent. of those under treatment at the city hospitals exhibited similar symptoms. Of these 69 per cent. were females.

Every symptom ascribed by Bullard to tea was found by Wood in his cases, who also found that the women manifested irregularities in menstruation of neurasthenic or hysteria type. He has found these symptoms to be produced by one-half of the quant.i.ty of tea charged with these effects by Bullard. The _Lancet_[161] several years ago, from an editorial a.n.a.lysis of the effects of tea-tippling, took the position that in no small degree nervous symptoms occurring in children during infancy were due to the practice of the mothers, both of the working and society cla.s.s, indulging in the excessive use of tea, the excess being judged by its effects on the individual and not by the amount taken. Convulsions and resultant infantile paralysis were frequently noticed among the children of these tea-tipplers. Observations among the factory population and the workers in the clothing sweating-shops show that tea neurasthenia, presenting all the ordinary symptoms of nervous exhaustion, is especially common among these.

It is evident that tea produces a grave form of neurasthenia readily transmissible to descendants. In addition to its effects directly upon the nervous system, tea tends to check both stomach and bowel digestion, and thus increases the self-poisoning which is so prominent a cause, consequence, and aggravation of these nervous conditions.

Coffee exerts a very similar action to that of tea, albeit the nervous symptoms produced by it are usually secondary to the disturbances of the stomach and bowel digestion. Coffee produces tremor, insomnia, nervous dyspepsia, and helmet sensations. With the exception of certain districts of the United States, coffee abuse is not carried to such an extent as tea, albeit in these, as in some portions of Germany, the habit is an excessive one. The conditions described result in Germany as frequently as they do in the United States. Mendel[162] finds that in Germany coffee inebriety is increasing and supplanting alcohol. Profound depression with sleeplessness and frequent vertex headache are early symptoms. Strong coffee will remove these temporarily, but it soon loses its effects, and they recur. There is much tremor, especially of the hands. The heart's action is rapid and irregular. Nervous dyspepsia is frequent. L. Bremer, of St. Louis, Mo., has observed similar conditions among both Germans and Americans there.

While coca took its place only recently among the toxic causes of degeneracy, it was old as a factor in the degeneration of the Peruvian long ere the discovery of America by Columbus. Forty-three years ago Johnston[163] wrote that even Europeans in different parts of Peru had fallen into the coca habit long practised by the Indians. A confirmed chewer of coca is called a _coquero_, and he becomes more thoroughly a slave to the leaf than the inveterate drunkard is to alcohol. Sometimes the _coquero_ is overtaken by an irresistible craving, and betakes himself for days together to the woods, and there indulges unrestrainedly in coca.

Young men of the best families of Peru are considered incurable when addicted to this extreme degree of excess. They abandon white society, and live in the woods or in Indian villages. In Peru the term white _coquero_ has the same sense as irreclaimable drunken tramp. The inveterate _coquero_ has an unsteady gait, yellow skin, quivering lips, hesitant speech, and general apathy. The drug has a.s.sumed an unusual prominence in the field of degeneracy since the discovery of its alkaloid, cocaine.

Since then there has sprung into existence in both Europe and the English-speaking countries the world over, a habit which, while much over-estimated, is undoubtedly growing, and aggravating as well as producing degeneracy. Many of the cases reported as due to cocaine are, however, chargeable to the desire of the hysteric or neurasthenic to secure a new sensation, or the desire on the part of the opium or whisky _habitue_ to try a dodge for forgiveness by friends. The habit is very frequently induced by patent medicines taken to cure catarrh by the neurasthenic, or to cure nervousness by hysterics as well. As the deformities of the nose pa.s.sages predispose to what is called "catarrh,"

patent medicines for local application containing cocaine are frequently employed in the treatment of this supposed const.i.tutional disease, with the result of aggravating the original degeneracy. As the youth under the stress of p.u.b.erty frequently ascribes all his ills to catarrh, he also employs very frequently snuffs containing cocaine, and has his nervous condition much aggravated thereby. Among the nostrums urged in the newspapers and magazines for this condition, so often resultant on nerve stress, is a certain notorious snuff containing 3 per cent. of cocaine.

From the description given by Johnson of the _coquero_ there can be no doubt but tramps, errabund lunatics, and paupers result from this habit, to give birth to degenerates in the next generation.

Lead has been found to produce in those exposed to its fumes a systemic nervous exhaustion, characterised by local paralysis about the wrist as well as the general symptoms of profound systemic nerve tire. This may result, as Tanquerel des Planches[164] pointed out nearly half a century ago, in acute insanity of the confusional type followed very often by forms of mental disorder of a chronic type resembling paretic dementia. In some cases the patient recovers from the acute insanity to suffer thereafter from epilepsy. In other cases, as Kiernan has shown,[165] an irritable suspicional condition results, in which the patient may live for years, marry, and leave offspring. This last condition and the epileptic are the most dangerous as to the production of degeneracy. As has already been pointed out, the women employed in the pottery factories in Germany suffer according to Rennert[166] from a form of lead poisoning which produces decidedly degenerative effects upon the offspring. These women had frequent abortions, often produced deaf-mutes, and very frequently macrocephalic children.

Bra.s.s workers suffer from a very similar nervous condition to that produced by lead. Hogden,[167] of Birmingham, called attention to the grave forms of nervous exhaustion produced among bra.s.s-workers. The period during which the patient is able to pursue the occupation without breaking down is longer than that of the lead workers. Women, like men, are exposed to this condition. The chief effect produced, so far as offspring have been observed, is chiefly frequent abortions and infantile paralysis.

The occupations employing mercury, whether mining, mirror-making, or gilding, produce forms of systemic nervous exhaustion in which the most marked symptom (but less important from a sanitary standpoint) is a tremor amounting at times almost to shaking-palsy. Like all other systemic nervous exhaustions, the mercurial one may appear as degeneracy in the offspring. The employment of women in match factories and tenement house sweating shops is growing. The chief toxic effect of phosphorus is not the localised jaw necrosis. This is but an evidence of the progressive system saturation with phosphorus. It bears the same relation to the more dangerous effects of phosphorus that "blue gum" does to the systemic effects of lead.

Every condition arising from a toxic cause capable of producing profound systemic nervous exhaustion in the ancestor, and especially the ancestress, is likely to be transmitted as degeneracy to the descendant.

Undoubtedly with the growing tendency of woman to pa.s.s from the ill-paid work of the seamstress to the better paid but dangerous occupations, a certain seeming increase in degeneracy must result.

CHAPTER VII

CONTAGIOUS AND INFECTIOUS DISEASE

Among the gains of human advance in evolution stand out prominently complete immunity from certain diseases due to germs, and partial immunity from others, which last immunity results in chronic types, rather than in acute, because of increased vital resistance in man. Tuberculosis and dourine, acute diseases in the cow and horse, have become chronic diseases, tuberculosis (or consumption) and syphilis, in man. Such chronicity is evidence of advance, yet it const.i.tutes an element of degeneracy, since the victim of the chronic disease is able to leave more offspring than would be possible were the disorder acute. In other respects acute and chronic contagions and infections exert the same influence in regard to degeneracy. The germ of the disease may be inherited, or general nutrition of the foetus may be so checked in development that the child inherits a predisposition to disease.

Through this check to foetal development the phagocytes, or white blood cells, become so weakened that they are unable to devour foetal structures as useless to man as the tadpole's tail (which it devours) is useless to the developed frog. This power being weakened, the organs which form ant.i.toxins (or protective tonics against disease), from lack of development fail to perform their function. For this reason in the degenerate many infections and contagions a.s.sume their old destructive type.

The influence of these disorders in the parent may result in the bony mal-development shown to occur in animals by Charrin and Gley, and in man by Coolidge. The facial bones, jaw, and teeth are peculiarly liable to be thus affected. Though the effect of the disease on the parent be but temporary, the child's development may be checked as to higher tendencies.

Thus mothers have borne moral imbeciles, epileptics or lunatics, after a pregnancy during which they were attacked by contagious disease, albeit the children of subsequent and previous pregnancies were normal.

The children of pregnancies previous to the one complicated by the contagious disease may be healthy, while those of subsequent pregnancies are defective. Any contagious or infectious disease may not only interfere temporarily with the bodily strength, but may produce complete change in the parent's system extending even to the highest acquirement of man. In some occur changes thus graphically described by Bulwer: "There have been men who, after an illness in which life itself seemed suspended, have arisen as out of a sleep with characters wholly changed. Before gentle, good, and truthful, they now become bitter, malignant, and false. To those whom they before loved they evince repugnance and loathing. Sometimes this change is so marked and irrational that their kindred ascribe it to madness. Not the madness which affects them in the ordinary business of life, but that which turns into harshness and discord the moral harmony which results from natures whole and complete."

The nerve centres controlling nutrition, growth, repair, secretion, and excretion are often as deeply affected as those checks const.i.tuting morality. At the periods of physiologic stress these effects are especially noticeable. Moral insanity, intellectual insanity, unequal mental balance, hysteria, precocious s.e.xuality, unconscious mendacity, mental parasitism (the germ of pauperism), epilepsy, neuroses, and all types of nutritive and const.i.tutional defects result. The nutritional defects may appear chiefly in the walls of the blood vessels and lymphatics. While these are most common in the chronic infections and contagions, they often occur in acute typhoid fever, scarlatina, diphtheria, whooping-cough, &c. Proper blood supply and utilisation of waste is thus prevented. Organs cannot perform their function, and are predisposed to disease from disuse and from weakness of the disease-fighting phagocytes and ant.i.toxins. From this results irregularity of organ function, which is hereditarily transmissible. The weakened vessel walls yield to strain, and thus produce local stomach, bowel, liver, gland, and kidney disorders. This organ weakness may alone be transmitted to the offspring. The functions of the great glands (thyroid, thymus, suprarenals, pituitary body, bone-marrow, t.e.s.t.i.c.l.es and ovaries) which secrete principles necessary to the equal balance of nutrition are perverted. The liver, in the acute but more particularly the chronic contagions, paralysed in nerve tone, fails in its function of poison-destroyer, as for the same reason the kidneys fail in their power of ejecting hurtful waste. Through this interaction of perverted nutrition, imperfect poison-destruction, and deficient waste ejection result and continue the states of nervous exhaustion after the contagions and infections. Thus nerve exhaustion with its suspicion, its capricious hopefulness and gaiety, is practically continuous in tuberculosis, syphilis, and leprosy.

The acute and chronic contagions and infections so lower cell vitality through the perverted functions described that inert connective tissue replaces healthy working cells. This is especially the case with syphilis, which, when driven from the system, leaves behind it a tendency to disease based on this connective tissue increase. This tendency, latent in the ancestor, may be so intensified in the descendant as to produce the hereditary ataxias (loss of movement power), and like neuroses. At the periods of stress such tendencies are peculiarly potent, and not only check, but reverse development. The chronic contagions and infections are most fertile sources of human degeneracy since their weakened products are enabled to survive under modern beneficence. Of these chronic contagions two (tuberculosis and syphilis) alone deserve attention, since the third (leprosy) exerts but little influence. Despite its existence for more than a century (New Brunswick and Nova Scotia on the north and Louisiana on the south) on the borders of the United States, despite its subsequent importation from Norway, Sweden, China, and Hawaii, its spread has been infinitesimal, and its influence on race deterioration is still less demonstrable.

Tuberculosis ("the white death") is from every standpoint a social danger more serious than syphilis. The father, as in syphilis, can infect the mother, but sterility is much less likely. As has already been shown in the chapter on heredity, plural and quickly repeated birth are common in tuberculous families. The tuberculous diathesis (or "habit," as Weismann calls it) was very early observed in the United States. Nearly seventy years ago W. P. Dewees, of Philadelphia, pointed out its frequency and its early observation by the Greek and Roman physicians. He cites a case ill.u.s.trative of the extent and uniformity of diathesis in a very numerous family. This predisposition arose on the side of the mother, though she lived herself to the age of forty-three, a period much exceeding that of any of her children, with the exception of a son, who died in his forty-fifth year. This lady bore twenty-three children without being able to suckle any but the two first. The males much exceed the females in number, yet there did not appear to be any exception to their favour in the transmission of the phthisical taint, except that they attained in general a greater age before they died. Some died about p.u.b.erty, others at manhood or womanhood; but all, with the exception just stated, under thirty. The disease was never very rapid; they generally complained from one to two years before they died. The men had a healthy, even in some instances an athletic, appearance until the disease became open and decided. In their growth and stature they altogether resembled the father, who was not only a remarkably stout man, but lived beyond the eightieth year. The females, who pa.s.sed p.u.b.erty (two in number) were rather stout women, while the mother was both delicate and small. This family lived in the country, was very wealthy, and always accustomed to the various means generally found successful either in destroying the predisposition or lessening its influence, yet in no one instance in this family were they successful, though the open form of the disease was r.e.t.a.r.ded perhaps in all. The females died the earliest.[168]

The blood vessel system is affected as regards development in such families. The heart is often diminutive; the right ventricle is exaggerated. Two great types of degenerate const.i.tutions are produced in children of the tuberculous. One of these may well come under De Giovanni's category of the torpid. The victim is usually coa.r.s.e-featured and coa.r.s.e-skinned, with peculiarly unstable mentality; slowness of comprehension is combined with power of continuity of thought; at times mental apathy alternates with quickness of perception. Decided exaggeration of the lymphatic system (connected with utilising of material elsewhere than at the point where it has been rendered unfit) with deficient function occurs, resulting in fitting a soil for germs. In other respects the torpid resembles the second type, the erethistic (nervously fussy type) of De Giovanni. This is generally characterised by the presence of a clear complexion, a fine skin, and features well cut and often beautiful. The lips are red and the teeth pearly white, though liable to early decay, and the eyes are large and full, the pupil being widely dilated and the white of the eye beautifully clear. The eyelashes are long, curved and silky, and the blue veins show distinctly through the clear thin skin. The bones are light, the hands and feet well formed, the stature often tall, and the whole figure slightly and gracefully built.

The erethists generally remain spare, and have a strong dislike to fatty food. They are vivacious and excitable, and the intellectual faculties are often highly developed. At an early age they show marvellous activity. The regularity with which such precocious tubercular children die has given rise to proverbs anent exceptionally clever children that they are "too wise to live long." Wanting in stamina, they are incapable of prolonged exertion either of mind or body, and break down under conditions which would not prove injurious to the healthy. They are continually taking "cold," and are p.r.o.ne throughout life to affections of an inflammatory character. Multiple and frequent pregnancies occur. The children, deficient in vitality, are carried off in numbers during infancy by convulsions, brain fever, water on the brain, exhaustion, diarrhoea, teething, and other ailments, or they succ.u.mb at the second detention or at p.u.b.erty. A small proportion reach maturity. Few live beyond thirty-five or forty years of age. However brilliant intellectually, they are equally emotional, impressionable, and impulsive. There is a marked absence of mental stability. They are suspiciously capricious. The great secreting and eliminating glands undergo with peculiar frequency the perversions already described.

Neuroses and psychoses are peculiarly frequent in childhood and youth. The degenerative power of tuberculosis is not always due to the influence of the germ, or even of the toxin produced by it, but to the state of nerve weakness resultant on the disorder. The victim of tuberculosis (especially if affecting the lung) is a suspicious, yet hopeful, nervous invalid, whose functions are irregularly performed and who is therefore likely to leave scions with greater defect, especially as the maternal factor, either through infection or worry, can hardly escape being weakened.

Tuberculosis attacks the bones of the offspring, especially the spine and hip-joint, but the victim of these last frequently regain health after apparent recovery from the local disease through surgical procedures. If the victim of the hip-joint disorder be of the erethist type marriage is not unlikely. Despite the deformity produced by spine disorder, popular superst.i.tion as to the "good luck" of a hunchback leads to marriage among the working cla.s.s. Monetary and social considerations effect the same result among the wealthy cla.s.ses. Here deformity does not prevent marriage, but predisposes to sterility through birth difficulty.

The influence of syphilis is, in a general sense, the same as that of tuberculosis, except that by reversing the principle of individuation it leads to greater sterility. Furthermore it exhibits greater tendencies to revert towards health, and yields (even in the inherited form) more to medicinal treatment. The inherited form at times presents itself in two types closely simulating those due to tuberculosis. Like the bacillus of tuberculosis, the syphilitic germ attacks every structure and organ of the body. Its reversal of the principle of individuation, causing excessive cell formation, produces more decidedly demonstrable effects. As syphilis is more apt to attack the central nervous system than tuberculosis, it would seem that it is a greater race-deteriorating factor. The excessive tendency to cell formation, however, produces impotence in man, sterility and abortion in woman. There are very good reasons for believing that the race is becoming immune to syphilis, and that this disease will disappear.

Its greatest race-deteriorating effect is in preparing the soil for tuberculosis and other infections and contagions.

The influence of contagions and infections on degeneracy is therefore by no means slight. Each disease can produce grave const.i.tutional defects in the ancestor likely to be intensified in the offspring. The greatest social dangers result from tuberculosis; the next from syphilis. Typhoid fever, scarlatina, small-pox, measles, diphtheria, whooping-cough, and all other contagions, however, may produce these const.i.tutional defects, either through the mother during pregnancy or through their secondary effects on the ancestor's const.i.tution. If the subject be attacked before the close of the periods of dental stress an arrest of development of the bones of the face may result with irregularities in the shape and position of the teeth. These, then, are stigmata of degeneracy, especially due, in the individual presenting them, to the contagions and infections rather than to inheritance alone.

CHAPTER VIII

CLIMATE, SOIL, AND FOOD

Among the factors const.i.tuting environment few have impressed the biologist so much as climate, soil, and food. The seeming modifications produced by these have made a very decided impression on the sceptical Weismann, who stated that "the possibility is not to be rejected that influences continued for a long time, that is, for generations, such as temperature, climate, kind of nourishment, &c., which may affect the germ plasm, as well as any other part of the organism, may produce a change in the const.i.tution of the germ plasm. But such influences would not then produce individual variations, but would necessarily modify, in the same way, all the individuals of a species living in a certain district. It is possible, though it cannot be proved, that many climatic varieties have arisen in this manner. Possibly other phenomena of variation must be referred to a variation in the structure of the germ plasm produced directly by external influences."

Considering the changes brought about in European plants and animals in Australia, those occurring in the East Indian mongoose in Jamaica, the changes in European plants and animals in America, or American animals in Europe and European animals in Asia, Weismann's position seems judicial.

The influences dependent on food, soil, and climate producing normal modifications have been remarkably ill.u.s.trated in the gilled batrachian Axolotl. This, under the nourishment and change of surroundings of the Jardin des Plantes, was transformed into a gill-less batrachian, which had hitherto been regarded as belonging to a totally distinct family.

According to Darwin,[169] English dogs degenerate in India in a few generations, losing the peculiarities of form and mental character which distinguish their particular race, in spite of the greatest care in selection and prevention of crossing. An instance which well deserves the consideration of those anthropologists who attach but little importance to the influence of the environment and to the value of speech as an aid to the ethnologist is that of the Wurtemburgers, who settled (1816) near Tiflis in Russia. They had originally fair or red hair, light or blue eyes and coa.r.s.e, broad features. In the first generation brown hair and black eyes began to appear; in the second black hair and eyes became the rule, while the face acquired an oval form. These changes were due entirely to the surroundings, no instance of crossing with Georgian natives being on record. At the same time, these transformed Wurtemburgers continue to speak their German mother-tongue uninfluenced by the local dialects.[170]

The alleged transformation of the British into the Yankee is commonly cited in ill.u.s.tration of the supposed effects of soil and climate. Three decades[171] ago Vogt remarked that American Anglo-Saxons or Yankees were instanced as ill.u.s.tration of change of character. Already, after the second generation, according to Pruner-Bey, the Yankee presents features of the Indian type. At a later period the glandular system is reduced to the minimum of its normal development. The skin becomes like leather; the colour of the cheeks is replaced by sallowness. The head becomes smaller and rounder, and is covered with stiff, dark hair; the neck becomes longer, and there is greater development of the cheek-bones and the ma.s.seters. The temporal fossae becomes deeper, the jaw-bones more ma.s.sive, the eyes lie in deep approximated sockets. The iris is dark, the glance is piercing and wild. The long bones, especially in the superior extremities, are lengthened so that the gloves manufactured in England and France for the American market are of a particular make, with very long fingers. The female pelvis approaches that of the male. According to Quatref.a.ges, America has thus, from the English race, produced a new white race which might be called the Yankee race. Vogt believes that America dries up the skin and reduces the fat, an effect to which all the above differences might be reduced. That the head becomes smaller he utterly denies. Exact cranial measurements by Morton show that the skull of the Yankee is at least as large as that of the Englishman.

Similar changes have been noted in the Anglo-Saxon Australians. The true explanation of this is that early rigorous environment tended to cause reversion to types not uncommon even now in Great Britain, Ireland, and Scandinavia, resultant on the admixture of primitive types to which reference has been made. The same error has been made about the pelvis as about the skull. The male pelvis in the American is approximating the female in accordance with advance, since, as Havelock Ellis has shown,[172] not only by his skull, but by his pelvis, modern man is following a path first marked out by woman. The skull of the modern woman is more markedly feminine than that of the savage woman, while that of the modern man has approximated to it. Not only is the pelvis of the modern woman much more feminine in character than that of the primitive woman, but the modern man's pelvis is also becoming more feminine.