NOTES ON THE FKEE-LIVING NEMATODES. 



465 



the distal limb. Possibly in accordance with this shortening" 

 there is no linear succession of egg's increasing regularly in 

 size in the anterior part of the gland, but each egg grows and 

 reaches its full size before the one next in order begins to 

 differentiate itself in s\'/jti from the other oogonia. After an 

 egg has passed out of the ovary and been fertilised, a period 

 of some length elapses before the next finishes its growth in 

 the ovary and travels through the receptaculum in its turn. 

 It is only in the early stages, however, that oviposition is a 

 slow process, for as the period of maturity advances, the 

 zone of egg-maturation increases in length, and oogonia are 

 able to start their growth long before the ovum in front is 



Text-fig. 8. 



ready to be fertilised. Tlie deliberate character of egg- 

 production in D. maupasi is responsible for the fact that few 

 individuals are seen with more than a single pair of eggs 

 contained in their uteri. 



Rhabditis gurnej'i. — When this species wns first 

 examined large numbers of adult individuals were obtained 

 from cultures of decaying flesh. Amongst these a few wei"e 

 seen which, judging by their size, had only just attained 

 maturity, but whose uteri and vaginte were occupied by dis- 

 organised eggs, as iu hermaphrodites, which have exhausted 

 their stock of spermatozoa. It was at first supposed that this 

 was such a species as Rhabditis mar ion is (cf. Maupas, 

 p. 512), in which a small number of females producing eggs 

 only occur together with the hermaphrodites. When, how- 

 ever, young immature worms were isolated, they were often 



