609 
but in older larvae, on the point of moulting, we observe close behind 
the excretory pore, situated ventrally, a distinct uterus and vagina. 
To mention some measurements: in a larva with a total length of 
10.25 mm., the excretory pore lies 3 mm. from the anterior extre- 
Fig. 5. 
Fig. 5. Anterior extremity of a 2, having just moulted. Total length 9,2 mm., 
catch N° 42. XX 75. 
mity and the vagina 0.75 mm. more backwards; in a larva 9.2 
mm. long the excretory pore lies 2.7 mm. from the anterior end, 
the vagina 0.62 mm. more backwards, whereas in-a larva having 
a total length of 7 mm., in which the distance between excretory 
