GREEFFIELLA' 



(Trichoderma Greeff, 1869; not Trichoderma Steph. 1835) 



CONTRIBUTIONS TO A SCIENCE OF NEMATOLOGV, XII 

 BY N. A. COBB 



United States Department of Agriculture 



In 1869, Greeff described an externally peculiar and very interesting 

 small animal form under the name Trichoderma. Though it proves 

 in the end to be internally a typical nema, it is only after many years 

 that the fact becomes fully established. The minute size of the species 

 and the fact that the setose cuticle obscures the internal organs, taken 

 together, have delayed a fuller understanding of the internal anatomy. 



Opportunity has occurred to reexamine a species of this genus in a 

 living condition, and the results are presented herewith. They serve 

 to establish the view that the genus comprises typical nemas pre- 

 senting striking relationships to Desmoscolex. Greeff 's original 

 discovery is commemorated by renaming the genus Greeffiella. 

 G. oxycaudata (Greeff) is retained as the type species. 

 Greeffiella, nom. nov. 



Trichoderma Greeff, Arch. f. Naturg., Berlin, v. 35, bd. 1, 1869. Not 

 Trichoderma Steph., 1835, or Swains., 1839. 



1-5 10.4 13. 56. 70. . 



Greeffiella dasyura n. sp. 3. 4 $.(>, 13. 15. " 9.s " The thin layers 

 of the transparent, colorless, hairy cuticle are traversed by about fifty-six 

 plain transverse annules, easy of resolution, which are not materially altered 

 on the lateral fields. The number of annules corresponds with the number 

 of encircling rows of somatic setae. While there are no wings opposite the 

 lateral fields, wing spaces are faintly indicated by a slight spareness, or absence, 

 of setae near the lateral lines ; this however is a faint feature extending only 

 from the neck to the anus, and is perhaps more pronounced on the female than 

 on the male. The contour of the body is crenate, especially toward the 

 head. There appear to be toward thirty small unequal cephalic setae on the 

 front of the head, disposed, apparently, in two closely approximated cir- 

 clets. These setae average to be about as long as the head is wide and are 

 apparently too numerous and crowded to permit of any exact order ; however, 

 about twelve of the anterior ones are spread outward and forward while 

 all the others spread out more or less backward. These somewhat curved, 

 rather slender, tapering acute, somewhat stiff cephalic setae are of the same 



1 This paper was published in the Journal of the Washington Academy of Sciences, 

 vol. 12, no. 13, pp. 229-303 (issued July 19, 1922). It is printed with changed pagina- 

 tion but without other material alteration. 



