82 



SHELLS AND SHELL-FISH. 



PART I. 



than equal to the entire length of the shell, while the 

 operculum is only rudimentary. A singular unde- 

 scribed shelly, just communicated to us by Mr. Stuch- 

 bury, is evidently intermediate between the shape of 

 the shells of Ehiirna and Struthiolaria ; so that this 

 part of our series is definite. We must now return to 

 Cyllene, for the purpose of showing its close approxi- 

 mation to the fourth genus^ Pseudoliva, the type of 

 which is the Buccinum plumheum of Linnsean authors. 

 The very aspect of this {^fig. 3. a) is quite sufficient to 

 show its proximity to 

 Cyllene, and its abso- 

 lute connection with 

 the VolutidfB by means 

 of Olivillahiplicata (&). 

 Last of all, as forming 

 a passage to the Py- 

 rulcBy we have Lati- 

 axis MawcB* (Sw.), 

 where thechannelround 

 the whorls is so broad that they become almost discon- 

 nected. At first sight, this shell would appear a mon- 

 strosity, did w^e not remember its prototype, Scalaria 

 pretiosa, not to mention the tribe of Tuhulihranchia. 

 We consider it therefore as perfect in its kind, related to 

 aU the types we have noticed by its channeled suture, to 

 Ehurna by its large umbilicus, and to Rapella (the first 

 genus of the PyrulhKv) by something, very difficult to de- 

 scribe, in its general shape. The whole sub-family may 

 therefore be defined as shells whose base is truncate, having 

 a channel more or less developed round the whorls, an 

 aperture contracted at its base, and generally either 

 emarginate as in Ehurna, or very slightly notched as 

 in Struthiolaria and Latiaxis : the inner lip is much 

 developed and spreading, without having a defined 

 margin. The following table will also exhibit some of 

 its analogies ; the group, as a whole, being evidently a 

 representation of the NassincB in the neighbouring 

 family of the Muricidce. 



* Griff. Cuv. pi. 25. figs. 3, 4. 



