794 



ON THE CH^TOSOMATID^, 



passes, by a narroM^ constriction, into the rectum (Fig. 37, re), a 

 wide, thin-walled tube lined with cuticle. This opens by the 

 anus (Fig.38, rt.) on the mid-ventral surface, at an average dis- 

 tance of 0-080 mm., from the posterior end, in the female; and 

 0*099 mm., in the male. 



Fig.40.— C/i. hasire/N. 

 Dorsal view of liead, showing arrangement of dorsal seta?, and the glandular 

 bodies {(//. ) lying above the pharynx; ( x 660). 



Nerve-cells and nerve-fibres are distinguishable in the proto- 

 plasmic tissue in the head. They seem to form an ill-defined 

 ring surrounding the constriction between the two pharyngeal 

 bulbs, and give off strands forward and backward. 



Lying above the pharynx, and embedded in the hypodermis, 

 there is a group of densely granular bodies (Figs. 30, 40, 41, 7/.), 

 staining dark blue, from each of which, a strand runs forward, 

 and apparently connects with the base of one of the dorsal set*. 

 One or several thickenings occur in each of these strands, towards 

 the anterior end. I have been able to observe these bodies only 

 in a few specimens, and have failed to determine their exact 



