366 



HOPLOLAIMUS 



as the body is wide, the strongly cutinized medium sized vagina extends inward 

 at right angles to the ventral surface half the way across the body. From to- 

 ward the ends of the valvular open- 

 ing four muscles pass obliquely to 

 the ventrally submedian regions 

 of the body, two forward and 

 two backward, two to the right 

 and two to the left. Furthermore 

 there are two transverse valvular 

 muscles attached near the ends 

 of the opening and fanning out 

 to the lateral parts of the body 

 wall, one right and the other 

 left, each partially encircling the 

 intestine. Each of the two out- 

 stretched uteri, about two body- 

 widths long and about one-fourth 

 as wide as the body, at its distal 

 extremity presents a spermatheca 

 three-fourths as wide as the body, 

 sometimes containing what appear 

 to be toward one hundred sausage 

 shaped sperm cells each some- 

 times having a bunch of chromo- 

 somes at ode end . These sperma - 

 theca are located at a distance 

 from the vulva two or three times 



as great as the diameter of the body. In the late autumn they are a very uni- 

 form feature of the adult females which have deposited no, or very few, eggs. 

 As thus far seen, the slender outstretched ovaries are about one-fourth as wide 

 as the body; both lie on the left side. They are narrow and somewhat cylin- 

 droid and contain one hundred or more ova arranged somewhat irregularly. 

 The male is like the female in form. The 



Fio. 4. Lateral and ventral views of the tail end of the 

 male of Hoplolaimus coronalvs n. sp. Treated with potas- 

 sium hydrate to obliterate non-cutinized structures. 



3.4 8.9 _ 13. M 97.3 



spicula are colorless. A portion of the - 2~ s ^~3~2. T5~ ~~~^2~2 " 



gubernaculum lies ventrad. (telamon of " 



Hall). See Fig. 4. There are no preanal ventral supplementary male 

 organs, and no ribs occur in the bursa. The striae of the bursa on the 

 ventral side are less distinct near the ventral line. The terminal lobe of 

 the bursa appears destitute of striation; if any striae are present they 

 must be exceedingly fine. The vas deferens appears to be about one-half as 

 wide as the body. The narrow cylindroid testis tapers a little, and at the blind 

 end is only one-fourth as wide as the body. The granular sperm cells seen in 

 the vas deferens are about one-tenth as wide as the body; the spermatocytes, 

 farther forward, one-eighth. 



Habitat: Found in soil immediately about a Mermis "nest," (Agamermis 

 decaudatd), Four Mile Run, Falls Church, Va., U.S.A. Nov., 1922. 



The movements of this nema are very slow. The limber body readily takes 

 on sharp sigmoid curves and is sometimes seen coiled; in fact the males can 

 coil rather closely. From this amended characterization it seems evident 

 the Hoplolaimus Daday (not of other authors) is a rather clearly marked 

 genus. A close relative of Hoplolaimus is Dolichodorus Cobb 1914. 



