3l6 SYRNOLOPSIS. 



lamellae, the second a single one. In consequence of this divi- 

 sion, the above species is placed among those having two 

 lamellie, and the figure of it given by Mr. Crosse (fig. 56) is 

 made a new species under the name of S. Grandidieri, because 

 of having only one lamella. I do not believe the distinction 

 wilt hold good, as these plicae are either developed or entirely 

 absent in the same species in Pyramidellidse. 



Unfigured Species. 



S. HAMYANA, S. ANCEYANA, S. GIRAUDT, S. MINUTA, all of 

 Bourguignat. Lake Tanganyika. 



