CHAP. III. THE PURPURIIOS. 71 



other. Vexilla represents, in outward form, and most 

 perfectly in colour, Harpula vexillum, just as Harpa 

 typifies the crowned volutes. Oniscia and Cyprcecassis 

 are perfect counterparts of each other; while Cassidaria 

 and Cassis complete this system of analogies. If any 

 doubt existed as to the absolute union of Oniscia and 

 Cassidaria in regard to affinity, it is set aside by a re- 

 markable shell obligingly sent me by Mrs. Stuchbury, 

 where the characters of both are united. This is of 

 much additional importance, because it shows that Cas- 

 sidaria does not form one of the five types of the <Cas- 

 since, but merely leads to them from the NassincB. 

 These, therefore, are the grounds upon which we have 

 adopted Mr. Stuchbury's genus Cyprcecassis. And while 

 we return his opponents our best thanks for stimulating 

 our attention to the subject, and thus detecting a mate- 

 rial error of our own, we sincerely trust that he himself 

 will prosecute his researches with the same ability and 

 with the same success ; to the true advancement of our 

 favourite science of MALACOLOGY.* 



(62.) The PURPURIN^E form the next sub-family 

 in our arrangement. They include shells whose general 

 form closely resembles the Buccinince, or whelks, but 

 with this difference, that the pillar, without being ele- 

 vated round the margin, is very much thickened, yet 

 always more or less flattened and depressed not, as in 

 the generality of shells, convex. This, in truth, is the 

 only character seen in the shells, by which this assem- 

 blage is in any way linked together. For the rest, the 

 spire is almost always very short; the aperture large and 

 wide; the inner lip not otherwise developed than by a 

 transparent polish spread over it, which is sometimes 



* I cannot pass over this opportunity of publicly expressing my obliga- 

 tions to his worthy brother, Mr. S. Stuchbury, of Theobald's Road, one of 

 the first commercial naturalists in London, for the free use he has always 

 given me of any interesting shells in his collection, without the necessity 

 of purchasing them ; a liberality not always met with. With him, I have 

 named a series of types of the greater part of the new genera here defined, 

 and I feel assured he will supply them to collectors on the most fair and 

 moderate terms. 



