92 Mr. F. E. Beddard on a 



times tliey are in front of the outermost of the two setfe, 

 sometimes in front of the innermost. 



The atrial pores are, as in Gordiodrilus elegans, upon seg- 

 ments xviii. and xix. From these segments the ventral 

 pairs of setse have disappeared. The pores are borne upon 

 two projecting folds of epithelium, which seem to have much 

 the same structure as in the last species. The external 

 characters are thus hardly different from those of Gordio- 

 drilus elegans. 



Internal Structure. 



The internal structure, while agreeing in most particulars 

 with that of the last-mentioned species, presents nevertheless 

 quite recognizable points of difference. 



In the alimentary canal the buccal cavity occupies the first 

 two segments and a part of the third. The supra-ossophageal 

 ganglia which lie in the third segment mark the commence- 

 ment of the pharynx ; the pharynx has, as usual, a strongly 

 muscular dorsal wall and occupies only one segment — the 

 fourth. The oesophagus passes from here to the xiiith seg- 

 ment, in which the intestine commences, and is divisible into 

 two regions. The first part, occupying segments iv.-viii. 

 inclusive, is very slightly vascular and the epithelial lining 

 is much folded ; after the viiith segment the walls of the 

 oesophagus are very vascular and not so much folded ; but 

 this latter character, though it occurred in two specimens 

 examined, may be perhaps accidental. If I had dissected the 

 worm only, instead of seeking the results obtained by dissec- 

 tion by a continuous series of longitudinal sections, I should 

 have put down the pharynx as occupying a much larger 

 number of segments than one. The tract of oesophagus in 

 fact which immediately follows the pharynx is covered 

 dorsally with a dense mass of septal glands ; these are absent 

 from the pharynx itself. These septal glands, which are so 

 common among the lower Oligoch^ta, extend back as far as 

 the viith segment, and there are traces of them in the viiith ; 

 but it is only in the vth segment that they form a dense 

 investment of the gut. In the ninth segment the oesophagus 

 gives off the single ventral diverticulum which distinguishes 

 this from any other genus of Oligochajta. 



The relations of the calciferous pouch are precisely as in 

 the last species ; in fact the description I have already given 

 of this body was largely drawn from sections of the present 

 species. 



