426 



UTERINE EFFERENT 



w dct: 



uwtte 



int 



Fig. ! Amended diagrams of the demanian system of 

 M etoncholaimus pristiurus (dorsal view) and Adoncho- 

 laimus fuscus (side view), modified from the diagrams 

 of zur Strassen and deMan respectively, eff int, 

 enteric or intestinal efferent; eff ut, uterine efferent; 

 vlv, vulva; ov dct, oviduct; gl cdl (3), the three caudal 

 glands; gl monl, the moniliform glands; porus, exit pores 

 of the demanian system. Notice that in each case the 

 uvette empties through a minute pore, the uvette pore. 

 The moniliform glands in pristiurus are 64-fold; in 

 fuscus 8- or 16-fold. 



Uterine Efferent. An examination of Met- 

 oncholaimus pristiurus (zur Strassen) furnishes 

 convincing evidence that the interesting female 

 organ described by zur Strassen is connected not 

 only with the intestine, as he discovered, but also 

 with the uterus by means of a tube (see eff ut, 

 Fig. 1) extending forward from the uvette, i.e. 

 from the "rosette" of zur Strassen. The evidence 

 is as follows: In many female specimens it is 

 possible behind the vulva to follow backward 

 from near the vulva a long, narrow, apparently 

 (not really) vacant space, reminiscent of the 

 uterine efferent of Oncholaimium appendiculatum 

 (see Fig. 3) which on more careful examination 

 proves to be a duct. This duct, however, is not 

 so refractive or of such uniform diameter as in 

 appendiculatum, and is even more difficult to see. 

 It varies slightly in diameter. Here and there 

 throughout its length it can be seen to have a thin, 

 double-contoured wall containing small but 

 definite, much elongated nuclei. This tube is 

 usually in a collapsed condition, more often pre- 

 senting its edge toward the observer, but some- 

 times not. When it is presented edgewise, one 

 may often detect in its thin wall the scattered 

 elongated nuclei, especially in specimens fixed 

 and stained in acetic acid methyl green; occa- 

 sionally nuclei can be seen also in other views. 

 Examining the requisite number of specimens 

 leads to the conclusion that from the uterus near 

 the vulva the duct arises dorsad as a broad tube, 

 directed backward, which narrows rapidly and ex- 

 tends along the right side of the nema, approxi- 

 mately along the right lateral chord though 

 not necessarily exactly opposite, and, expanding, 

 joins and envelopes the uvette. See Fig. 1. 



