174 BULLETIN OF THE 



anywhere the trace of a connection with the intestine. On general 

 grounds one would be inclined to believe that the single terminal open- 

 ing was that of a cloaca ; but no evidence of any connection between 

 the end of the intestine and this thin-walled portion communicating 

 with the dorsal sac was obtained. It must then remain for future 

 investigations to decide whether this is morphologically a cloaca or 

 merely a vas deferens. 



The hypodermis in the terminal papilla is composed of a single layer 

 of approximately cubical cells (Plate VII. Fig. 90). This is the only 

 portion of the body wall in which the boundaries of the hypodermal 

 cells can be seen. 



The spermatozoa are usually found in such enormous numbers that 

 it is difScult to make out their true shape. They appear much like 

 micrococci, and when seen alone (Plate IV. Fig. 55) are slightly oval, 

 highly refractive bodies 1 /x in diameter. The merest indication of a pro- 

 toplasmic envelope surrounding them is found in the shape of a very 

 narrow light peripheral zone. They stain very deeply, and their minute 

 size renders it impossible to recognize any structure in them. It is 

 probable that, as in other Nematodes, the spermatozoa undergo some 

 metamorphosis after being introduced into the body of the female. 

 From one individual spermatic masses were voided into the sea-water 

 in which it was kept. Thei'e was no sign of motion in the mass when 

 flattened under a cover glass, and when dried on a cover glass and 

 stained nothing besides the oval spermatozoa could be seen, except a 

 certain amount of coagulated fluid. 



There may be found in the dorsal sac as well as in the body cavity 

 of certain male specimens peculiar pale bodies, not easily stainable and 

 varying greatly in form. They are probably the same as those which 

 Biirger (p. 647) speaks of as " ovale Gebilde von mattem Glanze, an 

 denen nicht zu errathen war, ob sie gleichfalls Kerne oder Einlagerungen 

 bedeuten." Macerations show that they are probably parasitic Grega- 

 rinida, the various appearances obtained from sections being due to 

 their having been cut in difi"erent planes (Plate VII. Fig. 91). 



h. Female. 



I do not believe that any of the previous observers have had a fe- 

 male. Verrill ('79) described the posterior end in the "female" as 

 "subtruncatc with a small terminal papilla." This applies exactly 

 to some males, and, as Figure 56 (Plate IV.) shows, is very unlike the 



