GASTEROPODA. 



Type, S. typicus. Upper Coal Measures. Springfield, Illinois. 



Shell fusiform, smooth, body whorls contracted below into a 

 distinct straight canal, with an oblique plait on the columella. 



Agrees with Macrocheilus in its smooth surface and columella 

 fold, but differs in its fusiform outline, narrow aperture, and 

 distinct canal. In its general appearance resembles Fasciolaria, 

 but has only one instead of two or three columella folds, and is 

 destitute of ornamentation, and its outer lip is smooth within. 



Euchrysalis, Lambe. 

 Fossil, 6 species. St. Cassian, Austria. 



[Family Stiliferhlf.] 



The genera are : — 



Stilifer. — Dr. Fischer supposes that Stilifer, though living 

 like a parasite on the tegumentary system of the echinoderms or 

 their appendages, does not feed on their substance, as has been 

 supposed. Mr. Gwyn Jeffreys's impression is that it feeds on 

 the excretions of the echinoderms. 



Styltferina, Adams. 



Shell imperforated, ovate conical, thin, smooth; whorls many, 

 produced in a styliform spire ; nucleus sinistral ; aperture sub- 

 quadrate ; Up simple, straight. 



Distribution, 2 species. Japan. 



M. Freyer, of Trieste, is of opinion that Entoconeha (K. 

 murabilis), which is parasitic on Synapta diyitata, is the 

 embryonic condition of a species of Natica. 



Family III. — Cerithiaile.* 



Includes Cerithium [Rhinoclavis and Bittium), Triforis, 

 Potamides (Vicarya, Gerithidea, Terebralia, Pyrazus, and 

 Lampania), NERiNiEA, and the following additional genera 

 and sub-genera : — 



Cerithium. — Sub-yenus. Sandberyeria, Bosquet, 1860. 

 Dedicated to Professor Sandberger. Type, Cerithium cancel- 

 lata, Nyst. sp. Shell short, like Cerithium, canal terminal, 

 very broad, and short. M. Bosquet describes the type as 

 having an operculum as in Stenothyra ; it is very questionable 

 as to whether the operculum belonged to the shell. 

 * See p. 212, &c. 



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