Marine Protozoa from Woods Hole.

by Gary N. Galkins.

Comparatively little has been done in this country upon marine Protozoa. A few observations have been made by Kellicott, Stokes, and Peck, but these have not been at all complete. With the exception of Miss Stevens's excellent description of species of _Lichnophora_ I am aware of no single papers on individual forms. Peck ('93 and '95) clearly stated the economic position of marine Protozoa as sources of food, and I need not add to his arguments. It is of interest to know the actual species of various groups in any locality and to compare them with European forms. The present contribution is only the beginning of a series upon the marine Protozoa at Woods Hole, and the species here enumerated are those which were found with the algae along the edge of the floating wharf in front of the Fish Commission building and within a s.p.a.ce of about 20 feet. Many of them were observed in the water and algae taken fresh from the sea; others were found only after the water had been allowed to stand for a few days in the laboratory. The tow-net was not used, the free surface Protozoa were not studied, nor was the dredge called into play. Both of these means of collecting promise excellent results, and at some future time I hope to take advantage of them.

My observations cover a period of two months, from the 1st of July to the 1st of September. During that time I was able to study and describe 72 species representing 55 genera, all from the limited s.p.a.ce mentioned above. In addition to these there are a few genera and species upon which I have insufficient notes, and these I shall reserve until opportunity comes to study them further.

I take this opportunity to express my thanks to Dr. Hugh M. Smith for many favors shown me while at Woods Hole.

In dealing with these marine forms from the systematic standpoint, two courses are open to the investigator. He may make numerous new species based upon minor differences in structure, or he may extend previous descriptions until they are elastic enough to cover the variations. The great majority of marine protozoa have been described from European waters, and the descriptions are usually not elastic enough to embrace the forms found at Woods Hole. I have chosen, however, to hold to the conservative plan of systematic work, and to make as few new species as possible, extending the older descriptions to include the new forms.

The different cla.s.ses of Protozoa, and orders within the cla.s.ses, are distributed more or less in zones. Thus the Infusoria, including the Ciliata and the Suctoria, are usually littoral in their habitat, living upon the sh.o.r.e-dwelling, or attached, water plants and upon the animals frequenting them. It is to be expected, therefore, that in forms here considered there should be a preponderance of Infusoria. Flagellated forms are also found in similar localities, but on the Surface of the sea as well; hence the number described in these pages is probably only a small proportion of the total number of Mastigophora in this region. The Sarcodina, including the Foraminifera and the Radiolaria, are typically deep-sea forms and would not be represented by many types in the restricted locality examined at Woods Hole. Two species, _Gromia lagenoides_ and _Truncatulina lobatula_, alone represent the great order of Foraminifera, while the still larger group of Radiolaria is not represented at all.

The Protozoa described are distributed among the different orders as follows:*

Cla.s.s SARCODINA.

Subcla.s.s RHIZOPODA.

Order AMOEBIDA.

1. _Amoeba guttula_ Duj 2. _Amoeba_ sp.

3. _Trichosphaerium sieboldi_ Schn.

Order RETICULARIIDA.

Suborder IMPERFORINA.

4. _Gromia lagenoides_ Gruber.

Suborder PERFORINA.

5. _Truncatulina lobatula_ Walker & Jacob.

Subcla.s.s HELIOZOA.

Order APHROTHORACIDA.

6. _Actinophrys sol_ Ehr.

Order CHLAMYDOPHORIDA.

7. _Heterophrys myriapoda_ Archer.

Cla.s.s MASTIGOPHORA.

Subcla.s.s FLAGELLIDIA.

Order MONADIDA.

8. _Mastigamoeba simplex_, n. sp.

9. _Codonoeca gracilis_, n. sp.

10. _Monas_ sp.

Order CHOANOFLAGELLIDA.

11. _Monosiga ovata_ S. Kent.

12. _Monosiga fusiformis_ S. Kent.

13. _Codonosiga botrytis_ (Ehr.) J. Cl.

Order HETEROMASTIGIDA.

14. _Bodo globosus_ Stein.

15. _Bodo caudatus_ (Duj.) Stein.

16. _Oxyrrhis marina_ Duj.

Order EUGLENIDA.

17. _Astasia contorta_ Duj.

18. _Anisonema vitrea_ Duj.

Order SILICOFLAGELLIDA.

19. _Distepha.n.u.s speculum_ Stohr.

Subcla.s.s DINOFLAGELLIDIA.

Order ADINIDA.

20. _Exuviaella lima_ Clenk.

21. _Exuviaella marina_ Clenk.

Order DINIFERIDA.

22. _Gymnodinium gracile_ Bergh.

23. _Glenodinium cinctum_ Ehr.

24. _Glenodinium compressa_, n. sp.

25. _Peridinium digitale_ Pouchet.

26. _Peridinium divergens_ Ehr.

27. _Ceratium tripos_ Nitsch.

28. _Ceratium fusus_ Ehr.

29. _Amphidinium operculatum_ Clap. & Lach.

Cla.s.s INFUSORIA.

Subcla.s.s CILIATA.

Order HOLOTRICHIDA.

Family ENCHELINIDae.

30. _Lacrymaria lagenula_ Cl. & Lach.

31. _Lacrymaria coronata_ Cl. & Lach.

32. _Trachelocerca phoenicopterus_ Cohn.

33. _Tiarina fusus_ Cl. & Lach.

34. _Mesodinium cinctum_, n. sp.

Family TRACHYLINIDae.

35. _Lionotus fasciola_ Ehr.

36. _Loxophyllum setigerum_ Quenn.

Family CHLAMYDODONTIDae.

37. _Na.s.sula microstoma_ Cohn.

38. _Chilodon cucullulus_ Mull.

39. _Dysteria lanceolata_ Cl. & Lach.

Family CHILIFERIDae.

40. _Frontonia leucas_ Ehr.

41. _Colpidium colpoda_ Ehr.

42. _Uronema marina_ Duj.

Family PLEURONEMIDae.

43. _Pleuronema chrysalis_ Ehr.

44. _Pleuronema setigera_, n. sp.

45. _Lembus infusionum_, n. sp.

46. _Lembus pusillus_ Quenn.

Family OPALINIDae.

47. _Anoplophrya branchiarum_ Stein.

Order HETEROTRICHIDA.

Family BURSARIDae.

48. _Condylostoma patens_ Mull.

Family HALTERIDae.

49. _Strombidium caudatum_ From.

Family TINTINNIDae.

50. _Tintinnopsis beroidea_ Stein.

51. _Tintinnopsis davidoffi_ Daday.