108 



SHELLS AND SHELL-FISH. 



PART I. 



mantle, as in the Olivince. This,, in fact, is the only genus 

 which is neither spined, muricated, nor tuberculated. 

 The spire (6) is conic and somewhat short ; the whorls of 

 the apex are scarcely papillose ; while the inner margin 

 of the lip is considerably thickened. The plaits on the 

 pillar, as to number, are by no means constant, even in 

 the same species ; in general, there are four, but the last 

 is always the smallest. Sometimes, however, the pillar, 

 at this part of the aperture, is thickened, and there are 

 five or even six plaits confused and irregular*, as in S. 

 papillaris (Jig. 12. a). This latter type is remarkable for 



its apex, which is suddenly enlarged into a thick nipple- 

 like form (6), similar to Harpula fulminata, and very 

 much like the published figure of Valuta fulgetrum. 

 From this, it is clear that we have again arrived, almost 

 unconsciously, among the aberrant forms of the melon 

 volutes j for fulgetrum connects papillaris to magnifica, 

 which, with the form of fulgetrum, assumes, as it were, 

 that particularly large spire which is the chief character 

 of the genus Valuta. Scaphella papillaris, on the other 

 hand, is closely connected to our S. fusiformis, which 

 thus unites it also to S. undulata. 



(99.) Here we close our remarks on the affinities of 

 these magnificent shells ; but, before we enter upon the 

 consequences of this distribution, we shall endeavour to 

 meet some objections which may possibly be raised 



* This deviation is not uncommon in Scaphella undulata : four is the 

 usual number of the plaits ; but sometimes, as Lamarck observes, there are 

 two smaller and supernumerary ones. (Lam. Syst. vii. i. 245.) The same 

 variation is seen in Scaph. Junonia. 



