VOLUTILITHES muricina. 



Family, Volutidse. Sub-Family, Volutince, Nob. 

 {Genus Voluta, Lam.) 

 Generic Character. 

 Spiral wliorls regularly and gradually diminishing towards the 

 apex, which is always acute. Plaits of the pillar numerous, 

 always indistinct, generally evanescent, and sometimes want- 

 ing. Nobis. 



Type, Voluta musicalis ? Lam. 



Specific Character. 



Shell nearly fuciform, the base narrow and smooth; the upper part 



with longitvdhial, subcostated, spinous plaits : inner lip 



thickened, the last plait on the pillar very thick, and separated 



from the others, xehich are slender, and nearly obsolete, by a 



deep groove. 



Voluta Muricina. Lam. %s^ 7, 1, 350. E7icy. 3Ieth. pi. 383. 

 /•I- ^ 



The fourth principal division of the Lamarkian Volutes 

 has hitherto been found only in a fossil state ; unless, 

 indeed, the Voluta Braziliana really belongs to tliis type. 

 The species are very numerous, both in the London day, 

 and the Calcaire grassier of Grignon. They offer some 

 beautiful types of form, representing^ the conterminous 

 groups in this family, some of which we may hereafter 

 notice more particularly. The pre-eminent type may pro- 

 bably be the V. musicalis of Lamarck ; as yet, we only 

 know this fossil from descriptions and figures, but it has 

 obviously been confounded with several others. 



Lamarck has given a character so exquisitely finished of 

 V. muricina, that we have done little more than translate 

 his words. Our specimen appears to be from Grignon, and 

 was furnished to us with the following, by Messrs. Stuch- 

 bury, 33, Theobald's Road, Bedford Row. 



VOLUTILITHES pertusa. 



Shell subfuciform , and the base striated ; the upper part with thick, 

 remote, and somewhat nodulous ribs ; traversed near the suture 

 ivith lines of punctured strix ; inner Up thickened, plaits on 

 the pillar distinct, the last very strong, the two next smaller, 

 and the upper very slender. 



This species is certainly undescribed by Lamarck, nor do 

 we find it in Dr. Fleming's useful compendium of the 

 "Mineral Conchology." Our specimen has (he grey tinge 

 of the London clay fossils. Neither of these species are 

 typical ; as they represent the recent costated Volutes, in 

 the adjoining group. 



