Apr. 17, 1916 Two New Nematodes 125 



The eggs of Diplogasier aerivora, which are elliptical in shape, averaged 

 about 0.062 mm. in length and 0.0335 "im. in diameter. When freshly 

 deposited, they were dark brown in color, but became transparent as the 

 embryo developed. Segmentation often began before the eggs were de- 

 posited and the succeeding cell divisions could (fig. 3, F-M) be readily 

 followed throughout. The eggs were numerous and could be found lying 

 close together in groups of from about 6 to 30. The eggs hatched in 

 about 18 hours from the time segmentation was first noticed. Toward 

 the end of the egg stage the living worm (fig. 3, M) could be plainly seen 

 moving about within the egg wall. These movements became more 

 active until the worm finally ruptured the wall and escaped. 



At the time of hatching, the young nematodes (fig. 3, -B) of this species 

 averaged 0.2145 mm. in length. At this stage the sex organs could not 

 be distinguished, because of their poor development. In water cultures 

 the worms grew very rapidly and reached maturity in three to four days. 

 The females matured slightly in advance of the males (fig. 2, /). D. 

 aerivora never exceeded 0.5 mm. in length nor completed its life cycle 

 while within the termite (fig. 3, A). The nematodes remained in the 

 termite in this form for an indefinite length of time, but upon emerging 

 into moist soil they matured in about two days. 



Although molting occurred in this species as in D. lahiata, it was much 

 more difficult to observe; and, while it was not observed more than once 

 in any individual, it is probable that more molts did occur. Molting 

 required less time in D. aerivora than in D. lahiata, and the posterior 

 end of the nematode remained free throughout the process. 



In the older water cultures the adults became so numerous that they 

 appeared as a living mass to the naked eye. The females, which were 

 much larger than the males, averaged 0.99 mm. in length and 0.067 ni"^- 

 in diameter, while the males averaged 0.75 mm. in length and 0.046 mm. 

 in diameter. When free in moist soil, the worms became even larger; 

 the females (fig. 3, D) averaged 1.632 mm. in length and 0.1192 mm, in 

 diameter, and the males (fig. 3, E) averaged 1.1425 mm. in length and 

 0.0724 mm, in diameter. 



When reared in water cultures, the females appeared darker than the 

 males, but when found in the soil both sexes appeared pearly white. 

 The alimentary canal of the female, like that of D. lahiata, was spiral, 

 while that of the male was straight. The posterior end of the female's 

 body tapered into a long, threadlike process, but in the male th:>s process 

 was shorter and its body ended in an abrupt hook. 



Process op mating. — The process of mating in D. aerivora (fig, 2, L) 

 was much the same as in D. lahiata. The male clasped the female 

 slightly back of the middle of the body, so that its anal opening was in 

 direct apposition to the genital pore of the female. In mating, the pos- 

 terior end of the male usually completely circled the body of the female, 

 although exceptions occurred. Although many instances of mating 



