CHAP. IV. 



HARPULA, VOLUTILITHES, SCAPHELLA. 



107 



the Harpula fulminata, has much the shape of a Fascio- 

 laria, but with the top of the outer lip slightly angulated 

 and dilated, something in the same way as Valuta 

 Scapha and Cym. mitis. The enlarged, knob-like form 

 of its apex immediately reminds us of Voliita papillaris ; 

 while in its markings, and in the thickness of the outer 

 lip, internally, it perfectly resembles Scaph. undidata. 

 The numerous plaits, however, clearly show it is a Har- 

 pula. Another, our H. lyriformis, is the only recent 

 volute whose spire is longer than the aperture ; and a 

 third aberrant type, the H. hullata, stands at the con- 

 fines of this genus, and forms a passage to the next. 



(97.) VoLUTiLiTHEs, SO far as is yet known, is a 

 genus found only in a fossil state ; unless, indeed, Vo- 

 luta nucleus Lam., peculiar to the Australian seas, be 

 considered as coming within its limits : it exhibits 

 none of the delicate plaits on the pillar of Harpula ; so 

 that one half of its characters belong to that genus, and 

 the other half to this. The typical characters of Volu- 

 tilitlies have already been detailed (92.) ; and as we shall 

 particularly notice the subordinate types hereafter, we 

 may pass onward to the next group. 



{9^'^ The last of the primary divisions is the Aus- 

 tralian genus ScAPHELLA ; the best known type being 

 the Scaphella undulata {fig. 11. a). All of these hitherto 

 discovered, are natives of the South Pacific Ocean. 



We are not aware that any of these shells have an epi- 

 dermis, and their uniform smoothness leads us to con- 

 clude they are partly covered by the dilated lobes of the 



