THE NAUTILUS. 101 



1. Section.: Privatula. North America, 



Shell cylindric; lamellae few and small or none. 

 Type : P. corticaria Say. '' 



2. Section : Euhifidaria (Bif. s. str.). America, Polynesia. 

 Shell cylindric to turriculate ; lamellae typical. 



Type : P. hordeacea Gabb. »^ 



P. harbadensis Kiist (W. I.) 



P. grevillei Chitty (W. I.) and numerous others. 



P. exigua Ad. Mauritius. 



3. Section : Boysidia} Asia, Polynesia. 



Shell conic ; aperture very peripheric ; lamellae typical. 

 Type : P. hunana Grdl. (China.) 



P. strophostoma Mlldff. (Philippines.) 



4. Section : Albinula. America, Asia, Polynesia. 



Shell oblong or conic-ovate or cylindrical, colorless (contains 

 rather various forms and should be divided in groups.) 

 Type : P. contraeta Say. 



P. armigerella Reinh. (China.) 



P. recondita Tapp.-Can. (Japan.) 



P. pediculus Shuttl. (Japan, Samoa.) 



P. artensis Montrz. (New Caledonia.) 



P. meridioi talis Mlldff. (From description ; China.) 



5. Section : Vertigopsis. North America. 



Shell small, vertigo-like, albino; parietal lamellae rather short 

 and almost simple ; palatals near the margin. 

 Type : P. curvidens Gld. 



^= 



So much for the shells. Of the soft parts very little is known 

 as yet. But it is probable that further investigations will prove the 

 relations shown by the shells, which in general yield true evidences 

 of the natural position of their bearers. 



iBoettger, in v. Mcellendorff (Jahrb. Mai. Ges., 1884, p. 180, 181) proposes 

 the subgeneric name Gredleriella ; but Gredler himself sent me specimens with 

 the above. Dr. v. Mcellendorff ranges the group next to Scopelophila (P. kokeili 

 Rssm. and RosstncEssleri Schm.) ; but the resemblance is only external, from the 

 conic shape of the shells. In the configuration of the apertural parts and especially 

 the lamella it closely resembles P. contractu Say, while in Scopelophila they are 

 of quite a different type and wholly marginal. 



