MOLLUSCAN GtBNUS COCHLlTOMA. ^50 



The radula (text-fig. 6) lias the formula : — 



f 71. 1. 71. xl43. 



f, 78. 1. 78. xl23. 



The median tooth is short-cusped and much wider than that 

 of var, obesa. The first admedian has a stout but rather low 

 mesocone, a fairly well-developed ectocone, and only the faintest 

 trace of an entocone. It is probable, though not quite certain, 

 that it is less well-developed than in var. obesa. The basal plate 

 is uniforml}^ less deep than in the latter, broader and more 

 rectangular. Yery little difference can be noticed in the ad- 

 laterals. A curious abnormality was to be observed in f^. 

 Commencing at the sixteenth transverse row, a short series of 

 about three rows of teeth is dwarfed and crowded closely together. 



Text-figure 6. 



Coclilitoma zehra \'?a\ fulgurata . 

 Kcidula ; median and admedian teeth. 



The pharynx. — Four main jrjharyngeal retractors pass through 

 the subcerebral orifice and spread out in a broad fan- shaped 

 fascia which, as in var. ohesa, hns a semi-lunar insertion on the 

 postero-ventral surface of the pharynx. There is a short oeso- 

 phagus which passes insensibly into the crop. Internally a 

 greater complication of the internal longitudinal folds, a greater 

 frequency of transverse ridges, and a greater general thickness 

 enables us to assume that the crop starts about 10 mm. from the 

 pharynx. Measured from this point the crops of f^ and f^ are 

 39 ±3 and 26±3 mm. in length respectively. 



The salivary glands (text-figs. 7 & 8) differ extensively in 

 f^ and f^. In general they correspond to those described above. 

 The crop passes into the anterior part of the stomach., in f^ 

 abruptly, in f^ gradually. The stomach exhibits considerable 

 differences in f^ and f.^. Thus in f^ the shape is piriform and 

 in f, irregular. But there is no character which differentiates 

 these forms from var. ohesa. 



The relation between the anterior and postei^ior parts of the 

 stomach (or stomach and cjecum) has not been commented upon 

 at any length save in a general way by Wiegmann (1898). The 

 stomach as a whole is bent on itself, and the apex of the bend is 



