26 ROCHESTER ACADEMY OF SCIEN'CE. [NoV. 23, 



to some variety and on this account several specific names have been 

 given to it, but they are seen to intergrade when an abundance of 

 material is examined and the names therefore cannot stand. 



97. Latirus polygonus, Gmel. Common. 



98. " sp. Common. 



99. " (Peristernia) nassatula, Lam. 

 A common shell, subject to extreme variation. 



100. Latirus (Peristernia) incarnata, Desh. Common. 



Family BUCCINIDi^. 



lOi. Tritonidea undosa, Swains. 



102. Pisania marmorata, Reeve. 



103. " ignea, Gmel. 



All three of the above forms are abundantly represented. The 

 specimens of Tritonidea undosa are exceptionally large and fine, and 

 covered by a short, brown, silky epidermis. 



Family NASSID^E. 



104. Buccinanops (Bullia) mauritiana, Cxray. 



A very characteristic species, distinguished at once by the double 

 callous running round the whorls, one above and one below the 

 suture ; the whorls are flat-sided instead of being rounded as in the 

 nearly related species. Buccinopsis Grayi, Reeve, is probably syn- 

 onymous. 



105. Nassa coronata, Brug. 



The characteristic light spiral bands, one above and one below 

 the periphery, are not always developed, and the shell is then of a 

 light drab color. The columellar callous is very large and spreading 

 in the specimens before me. 



106. Nassa (Alectrion) hirta, Kien., var. crenulata, Reeve. 



I can scarcely consider crenulata an absolute synonym of hirta as 

 Tryon has done. 



107. Nassa (Alectrion) papillosa, Linn. 



