S. Yokogawa 
137 
Plate VIII). They are found in the dorso-lateral regions of the body. One of 
them is located at a distance of 0-06 to 0*08 mm. from the base of the oeso¬ 
phagus, and the other about the same distance behind the anterior one. These 
glands seem to have developed from the large pear-shaped cells, which were 
found in the first stage on the ventral side of the region where the oesophagus 
joins the intestine. The excretory pore opens at the ventral side at a distance of 
0*13 mm. to 0*135 mm. from the anterior end of the body. Although the cervical 
gland-cells may be connected with the excretory pore at this stage, I could not 
trace any such connection clearly. 
Text-fig. 2. Development of the genital primordium during the free-living stage and at the 
beginning of the first parasitic stage, a. From newly hatched larva; b, during the first moult; 
c-h, shapes assumed during the second larval stage; i-l, shapes assumed during the first 
part of the first parasitic stage, 15 hours after infection. 
The genital anlage. The genital anlage (Fig. 6, gp, Plate VIII) is represented 
by an ellipsoidal or somewhat spindle-shaped transparent body which is 
situated ventrally in the region of the fourth or the fifth cells of the intestinal 
wall. Usually there can be seen beside the genital anlage a dark granular body 
as shown in the figures (Text-fig. 2). This body is so close to the genital anlage 
that it seems almost to be a part of it. I have, however, not succeeded in 
identifying this body in later development. The genital anlage consists of 
6 to 8 cells and measures 0*0012 to 0*0017 mm. by 0*007 to 0*008 mm. It is 
impossible to distinguish the sexes at this stage. 
Table II shows the size of the various parts of the larvae at this stage. 
