168 Rev. L. Guiiding on the Zoology of 



A subgenus which may receive those Clausilice which are edentate, 

 and without the Clausium or elastic operculum. I am convinced of the 

 necessity of restricting rigidly the generic characters of the terrestrial 

 Mollusca: and no apology will be necessary for the introduction of many 

 new titles in these essays, in as much as Mr. Vigors and my friend Mr. 

 Swainson have already in this Journal so ably silenced the clamour raised 

 against the multipHcation of genera by those who presume to call them- 

 selves the legitimate disciples of Linne — ^the faithful followers of that 

 great master, who was for nothing more remarkable than the fearless 

 manner in which he pulled down, new modelled, and built upon, the 

 works of those who had preceded him : and who confessedly left, after 

 his unexampled labors, nothing but the bare vralls of that edifice which 

 he well knew would require ages for its completion. 



Familia. Bulimid^e, Guild 



Genus. Macroceramus,* Guild. Pupa, et Bulimus?, Auctorum. 



Char. gen. 



Ani m al heliciforme, terrestre : caput subbilobatum. Tentacula quatuor, 

 duobus superioribus capitatis, oculigeris. Pes brevis, postice attenuatus, 

 simplex. 



Testa cylindrico-conica, crassa, opaca, umbilicata; anfractihus sen- 

 sim decrescentibus. Apertura regularis, semiovata; lahro subito reflexo. 

 Columella laevis, simplex. 



Macroceramus signatus. 



M. fuscescens, collo nigro-lineato : pedis lateribus nigricantibus : pallio 

 fuscescente, ferrugineo picto : oculis atris: disco gressorio pallido. 



Testa pallida, longitudinaliter subplicata: anfractibus undecim, litera 

 /3 seriatim signalis: ultimo brunneo fasciato. 



Habited in Insula Tortola. Communicavit Dominus Shew. 



* Nomen a fiaxpoQ longus et Kepafiog testa. 



f I know not whether the use of the teeth and laminae of the Pupad<s has 

 been explained ; they may answer the purpose of an operculum to keep out 

 enemies, while they afford no obstacle to the motions of the soft and yielding 

 foody of the animal. 



