Total length, 485-515; tail, 54-68; hind foot, 108-111; ear from notch (dry), 60-63. Pelage coa.r.s.e; upper parts brownish gray; skull ma.s.sive; posterior extensions of supraorbital processes varying from those that project free to those that have the tips, or tips and a considerable part of the processes, attached to the braincase.

SYLVILAGUS CUNICULARIUS CUNICULARIUS (Waterhouse).

1848. _Lepus cunicularius_ Waterhouse, Nat. Hist. Mammalia, 2:132, type from Zacualpan (probably in state of Mexico).

1909. _Sylvilagus cunicularius_, Nelson, N. Amer. Fauna, 29:239, August 31.

1890. _Lepus verae-crucis_ Thomas, Proc. Zool. Soc. London, p. 74, June, type from Las Vigas, Veracruz.

_Marginal records_ (Nelson, 1909:241).--Hidalgo: Tulancingo.

Veracruz: Las Vigas; Orizaba. Oaxaca: Mt. Zempoaltepec; Suchixtepec.

Guerrero: Chilpancingo. Michoacan (Hall and Villa, 1949:469).

Patzcuaro; Tancitaro.

SYLVILAGUS CUNICULARIUS INSOLITUS (J. A. Allen).

1890. _Lepus insolitus_ J. A. Allen, Bull. Amer. Mus. Nat. Hist., 3:189, December 10, type from plains of Colima, Jalisco.

1909. _Sylvilagus cunicularius insolitus_, Nelson, N. Amer. Fauna, 29:243, August 31.

_Marginal records_ (Nelson, 1909:244).--Sinaloa: Mazatlan; Rosario; Esquinapa. Nayarit: Acaponeta. Colima: Colima; Armeria, thence northward along Pacific Coast.

SYLVILAGUS CUNICULARIUS PACIFICUS (Nelson).

1904. _Lepus veraecrucis pacificus_ Nelson, Proc. Biol. Soc.

Washington, 17:104, May 18, type from Acapulco, Guerrero.

1909. _Sylvilagus cunicularius pacificus_, Lyon and Osgood, Catal.

Bull. U. S. Nat. Mus., 62:35, January 28.

_Marginal records_ (Nelson, 1909:242).--Guerrero: El Limon. Oaxaca: Llano Grande, thence westward along Pacific Coast.

=Sylvilagus graysoni= (J. A. Allen)

Tres Marias Cottontail

1877. _Lepus graysoni_ J. A. Allen, Monogr. N. Amer. Rodentia, p.

347, August, type from Tres Marias Islands, Jalisco; probably Maria Madre Island. (See Nelson, N. Amer. Fauna, 14:16, April 29, 1899.)

1904. _Sylvilagus_ (_Sylvilagus_) _graysoni_, Lyon, Smiths. Misc.

Coll., 45:336, June 15.

_Marginal records_ (Nelson, 1909:245): Maria Madre Island; Maria Magdalena Island.

Total length, 480; tail, 51; hind foot, 99; ear from notch (dry), 57.

This insular species is closely related to _Sylvilagus cunicularius_ of the adjacent mainland but has notably shorter ears and more reddish on the upper parts, sides and legs; the skull is slenderer, especially in the rostral region. The posterior extensions of the supraorbital process are united to the braincase throughout most of their length as in _Sylvilagus pal.u.s.tris_. The species seems to have a narrow vertical range, occurring from sea level up to only 200 feet.

Genus LEPUS Linnaeus--Hares and Jack Rabbits

Revised by Nelson, N. Amer. Fauna, 29:59-158, August 31, 1909.

Concerning Shamel's (Proc. Biol. Soc. Washington, 55:25, May 12, 1942) proposed changes of names for several species, see Hall, Univ.

Kansas Publ., Mus. Nat. Hist., 5:45, October 1, 1951.

1758. _Lepus_ Linnaeus, Systema Naturae, ed. 10, 1:57. Type _Lepus timidus_ Linnaeus.

1895. _Macrotolagus_ Mearns, Science, n. s., 1:698, June 21. Type, _Lepus alleni_ Mearns. (See Mearns, Proc. U. S. Nat. Mus., 18:552, June 24, 1896.)

1904. _Poecilolagus_ Lyon, Smiths. Misc. Coll., 45:395, June 15.

Type, _Lepus america.n.u.s_ Erxleben.

1904. _Lagos_ Palmer. N. Amer. Fauna, 23:361, January 23. Type, _Lepus arcticus_ Ross. _Lagos_ J. Brooks, a catalogue of the anatomical and zoological museum, pt. 1, p. 54, July, 1828, appears to be a _nomen nudum_.

1911. _Boreolepus_ Barrett-Hamilton, History of the British Mammalia, pt. 9, p. 160, November 17. Type, _Lepus groenlandicus_ Rhoads. (For status see Sutton and Hamilton, Mem. Carnegie Mus., 12 (pt. 2, sec. 1):78, August 4, 1932; also A. H. Howell, Jour.

Mamm., 17:331, November 16.)

Total length, 363-664; tail, 25-112; hind foot, 112-189; ear from notch (dry), 62-144. Upper parts grayish, brownish or black; interparietal bone fused to surrounding bones; cervical vertabrae long, 2nd and 3rd being longer than wide; transverse processes of lumbar vertabrae long, the longest one equal to the length of the centrum to which it is attached plus half of the length of the preceding centrum; free extremity of transverse process of lumbar vertebra considerably expanded; distance from anterior edge of acetabulum to extreme anterior point of ilium less than distance from former point to most distant point of ischium; ulna reduced in size along middle part of shaft, and, excepting the lower extremity, placed almost entirely behind radius.

All members of the genus _Lepus_ are technically hares, as these are defined in the account of the family Leporidae. The largest members of the order Lagomorpha are members of the genus _Lepus_. No domestic strains have been developed but effort in this direction might be profitable, in as much as the so-called Belgian hares of the related genus, _Oryctolagus_, have done well in captivity.

In the past it has been customary to recognize two or more subgenera of the genus _Lepus_. The species are a less diverse lot than those in some other genera, however, and it seems that no useful purpose is served by recognizing subgenera. Accordingly, the several names proposed for this purpose are arranged here as synonyms of the generic name _Lepus_ Linnaeus.

The introduction of the European Hare (_Lepus europaeus_) into the eastern part of the North American Continent has been successful in the sense that the animal is multiplying. If it continues to increase, the increase almost certainly will be at the expense of some native species of rabbit. This circ.u.mstance and the unfortunate consequences of the introduction of the European rabbit (_Oryctolagus cuniculus_) in New Zealand (see Wodzicki, 1950:107-141) and Australia (see Stead, 1925:355-358) give basis for effort to exterminate the alien species before it spreads more widely.

KEY TO THE SPECIES OF THE GENUS LEPUS

1. North of 34 N lat.i.tude.

2. All white pelage (tips of ears sometimes black).

3. North of line from Port Simpson, British Columbia, to Halifax, Nova Scotia.

4. Basilar length of skull more than 67; ear from notch usually more than 73 dry (77 fresh); first upper incisors inscribing an arch of a circle the radius of which is more than 9.6 mm.

5. Geographic range east of Mackenzie River.

_Lepus arcticus_, p. 178

5'. Geographic range west of Mackenzie River.

_Lepus othus_, p. 177

4'. Basilar length of skull less than 67; ear from notch usually less than 73 dry (77 fresh); first upper incisors inscribing an arch of a circle the radius of which is less than 9.6 mm.

_Lepus america.n.u.s_, p. 173

3'. South of a line from Port Simpson, British Columbia to Halifax, Nova Scotia.

5. Ear from notch more than 82 dry (87 fresh); least interorbital breadth more than 26 _Lepus townsendii_, p. 180