28G MAZATLAN rXlVALTES 



adult state, stould be so different in tlieir early stage, is very 

 remarkable. A series of specimens from the inside of a West 

 African Pinna, of wbicb the youngest is only "04 long, agree 

 exactly with the Mazatlan specimens now described. The 

 largest, 1'18 in length, would certainly have been called C. 

 squama if from Panama, though the epidermis is thinner than 

 in the ordinary INIazatlan specimens. They go through the same 

 changes of colour, deck margin, &c. as C. nivea ; and if they 

 had been born in an empty Cowry woidd probably have deve- 

 loped into the genuine C. 'unguiformis. As it is, they are 

 probably the C. Goreensis,* a species which, according to 

 DUlwjTi, has a tendency (like C. nivea) to develop foliations. 

 Whether the specimens quoted by Mcnke as C. Goreensis 

 belong to this species or to C. squama, cannot be told without an 

 examination of the vertex. Shells of exactly the same species, 

 some extremely young and well formed, others of the true C. 

 unguiformis shape, circular and elongated, were found in dead 

 East Indian Cowries from Singapore The species may abound 

 at Mazatlan ; but as almost all the vast numbers of shells sent 

 were perfectly fresh, there is no knowing what the dead ones 

 contained. The largest Mazatlan shell with the apex perfect 

 measures long. '12, lat. "OS, alt. '02. Others, which have lost 

 the apex in growth, may belong either to this species or to 

 C. nivea. 



Hah. — Mediterranean, Africa, Singapore, North and South 

 America, East and West ; fossil in tertiary strata ; i\ supra. — 

 Callao, Peru, very fine, in dead shells, B. M. Col. D' Orbigny, 

 not in Cat. — Mazatlan ; extremely rare, in dead shells, &c. ; 

 Upool Col. 

 Tablet 14:30 contains 3 sp. yoimg. — 1431, an adult sp. in 



empty Trivia radians. 



Genus CRUCIBULUM, Schum. 



Cnicibulum, Schum. Ess. no. 8, 1817 : — Gray, Proc. Zool. Soc. 



1817, p. 157, no. 270 i—H. 4' A. Ad. Gen. vol. i. p. 365. 

 Dispotoea, Say, Journ. Ac. N. S. P/iil. vol. iv. 1124. 

 Calypeopsis, Lesson, 1830, Brad. 1834. 



• The young of Cr. fomicata, as appears from specimens from Stat en lilsnd 

 in the collection of ]{. M' Andrew, Esq. is of the type Cr. Goreensis, &mel. but 

 with only one large tumid whirl f;is in CruoibuUim Lmbricatum,) lying imbedded 

 iu the normal portion. Inaidc with first deck at an angle with the succeeding. 



