48 PROCEEDINGS OF THE ACADEMY OP 



Nevilli. We have elsewhere described the dentition of G. sulcata, 

 Miill. (Ann. N. Y. Lye. N. H., x. 222). 



No jaw was found in any of the above, nor in Ennea clavulata, 

 Lam This last sjiecies is placed in s. g. Gulella by von Martens. 

 There were five embryonic shells in the oviduct, proving the 

 species to be viviparous. The dentition is the same as in Gonos- 

 pira. There appears to be a median tooth of same form as the 

 laterals. 



Of the genus Nanina (using the name in the same sense as von 

 Martens in die Heliceen), there were several species. All have the 

 locomotive disk, the caudal pore with overhanging horn-like projec- 

 tion, the smooth jaw with median projection, and the lingual denti- 

 tion of the genus, ^. e., centrals tricuspid, laterals bicuspid, mar- 

 ginals aculeate, bluntly bifid. Such are N. Caldwelli, Benson; N. 

 Baivsonis, Barclay = semicerina, Morelet ; X. argentea, Rve. ; N. 

 implicata, Nevill ; N. stylodon, Pfr., put in Flelix {Erepta) by von 

 Martens. Entirely different in the dentition is another species, N. 

 philyrina, Morelet, though the species agrees in other respects with 

 the above-named. The membrane is very broad, the teeth exceed- 

 ingly numerous, arranged in oblique rows. The centrals, which 

 I am confident of having seen, are small, narrow, high. The other 

 teeth are the same in form to the edge of the membrane. They 

 appear to have the usual aculeate form of the marginal teeth in 

 Nanina, but instead of narrowing towards the cutting point, they 

 are broadly and obliquely truncated, reflected, and minutely den- 

 ticulated. This lingual membrane is also figured by Semper (Phil. 

 Archip., pi. vi. f. 35), but his figures give more the impression of 

 the usual Nanina marginals with denticulated side and bifid jjoints. 

 The teeth are, however, so exceedingly numerous and small, it is 

 very difficult to understand them. 



Elsewhere (Ann. N. Y. Lye. X. H., x. ITO) we have described 

 the lingual of the following Mauritius species : Nanina inversi- 

 color, leucostyla, rufizonata, militaris. I have examined the geni- 

 talia of N. inversicolor. The oviduct is long, narrow, sac-like j 

 the genital bladder is hardly smaller than its long wide duct; the 

 penis sac is long, extended into a flagellum, receiving the vas 

 deferens near its apex, be^'ond it having a bulb-like termination ; 

 the vas deferens is greatly swollen at its middle portion, and near 

 the base of the oviduct has a long flagellate appendix. 



