BY E. J. GODDARD. 



339 



In the extended condition it is pear-shaped in outline, with a 

 convex dorsal, and flat ventral surface. The greater portion of 

 the ventral and dorsal surfaces are marked with grooves which 

 divide the body into areas corresponding to the somites, as is 

 found on more detailed examination. 



The colour is a pale green. 



The anterior portion of the body possesses numerous sets of 

 sense papilla?. 



The first somite is uniannulate, the second biannulate, and 

 the remaining somites triannulate. 



Fig. 11. — Semilageneta HUH, gen.et sp.n. 

 Dorsal view. (Drawn from a photograph). 



The head is constituted by eight annuli, the ninth annulus 

 forming the posterior margin of the anterior sucker. Around 

 the margin of the sucker, and on each of the annuli composing it 

 are papillce which are much larger than the other sensory 

 papillae, and probably represent goblet organs. 



Fig. 12.— Semilageneta HUH, gen. et sp. n. 

 Ventral view. (Drawn from a photograph). 



The sense papillae occur on the first annulus of each somite, as 

 Whitman found to be the case in the leeches he examined. 

 Castle, however, in his careful work on American Rhynchob- 

 dellids, came to the conclusion that the papillae denoted not the 



