66 CANCELLARIA. 



Subgenus ADMETE, Kroyer. Shell oval, thin, diaphanous, with 

 epidermis, spire sharp, last whorl slightly ventricose ; aperture 

 oval, feebly sinuated in front, coluraella obliquely truncate, sub- 

 plicate in front, lip sharp (A. viridula, Fabr.). 



Subgenus ADMETOPSIS, Meek. Anterior plication of the colu- 

 mella more elevated than the posterior one ; lip thick ; shell 

 otherwise resembling Admete (A. gregaria, Meek). 



In the present work I have ranged all the groups under one 

 genus Cancellaria, regarding Admete as the only recent sub- 

 genus. The typical Cancellariae are thus classified : 



Section CANCELLARIA (== S. G. Cancellaria and Merica of 

 Fischer). 



Subsections EUCLTA ; MERICA (including Massyla and Aphera); 

 NARONA. 



Section TRIGONOSTOMA (= S. G. Trigonostoma of Fischer). 



Descriptions of the animals of Cancellaria Spengleriana, 

 C. cancellata, and Admete viridula, will be found under those 

 species in my text. 



Seventy-eight recent species are enumerated by Messrs. 

 Adams ; thirty by Kiener (Coq. vivantes) ; sixty -eight by 

 Sowerby (Thesaurus Conchyliorum) ; eight3 T -three by Reeve 

 (Conchologica Iconica) ; Crosse (" Etude sur le genre Cancel 

 laire," Jour, de Conch., 220, 1861) has ninety-three recent and 

 eighty-one fossil species. Kobelt has commenced a monograph 

 of the genus in Kiister's Conchylien Cabinet ; only a few pages 

 and figures have as yet appeared. 



One hundred and seventy-four specific names enter into the 

 present work, of which seventy-seven are recognized as valid 

 species, twenty-three are classed as doubtful and unidentified ; 

 the balance are considered synonyms. 



Genus CANCELLARIA. Lam. 

 Section CANCELLARIA, ,s. utricto. 



C. CASSIDIFORMIS, Sowb. PI. 1, fig. 1. 



Orange-fulvous or flesh-color, often indistinctly light-banded 

 on the middle of the body-whorl. Length, l'5-2'5 inches. 



Panama to Gulf of Mexico. 



