Shells of this genus are also frequent among the Veronese and Vinceq- 

 tine fossils. 



Lamarck enumerates ten species among the fossils of Grignon, Chau- 

 mont, &c. : T. imbricatarla, T. sulcata, T. subcarinata, T.fasclata, T. mul- 

 tisulcata, T. terebdlata, T. perforate, T. unisulcata, T. uniangularis, T. me- 

 l&noides. 



XLIV. Pupa. A somewhat cylindrical univalve ; the last turn of 

 the spire, which is somewhat produced, not being larger than the pre- 

 ceding : the aperture irregularly roundish or oval : the margin continued 

 circularly. 



Turbo uva, Linn. Born. Vign. Fig. E. is the type of this genus, which 

 does not appear to be known fossil. 



XLV. Janthina. A subglobose diaphanous univalve: the opening 

 triangular, with an angular sinus on the right edge. 



Helix janthina, Linn. List. Tab. 572, Fig. 24, is of this genus ; *io 

 shell of which has, I believe, been found fossil. 



XL VI. Bulla. An ovate, gibbous, and somewhat cylindrical uni- 

 valve : the spire not standing out, but concealed within : the opening 

 the length of the shell : the lip acute. 



Bulla aperta, Linn, and Bulla lignaria, Linn, are contained within the 

 membranous part of the molluscse by which they are produced, so that 

 these molluscae appear naked, or without any external shell ; but the 

 lively colours, and the repeated convolutions of other species, as Bulla 

 ampulla, Linn. &c. show that these have not been contained within the 

 soft part of the animal. Lamarck, apprized of this circumstance, has 

 separated the former animals from the genus Bulla, and has formed with 

 them a genus of the naked molluscse, and named it Bull&a , leaving in 

 the genus Bulla those species, the shells of wbich, possessing the above- 

 recited generic characters, form the external covering to the animal. 



I do not know of any .English fossil shells of this genus. Respecting 

 Bulla sopita, Brand. Fossil Hanton. Fig. 29 a. and Bulla volutata, Brand. 

 Fossil. Hanton. Fig. 75, another, and apparently a more appropriate 



VOL. III. M 



