53 
C. stromho'ides, Lam. being subfusiform and transversely striated, 
with a nodular spire : the nodules, however, appearing to be more 
projecting, and turns of the spire more acute, than in the shell de- 
scribed by Lamarck. 
IX. Cyprcea. An ovate convex univalve, with the margins invo- 
luted ; spire small, and nearly covered over ; the opening long, 
narrow, and toothed on both sides. 
hen we consider that the markings of the recent shell of the genus 
Cypra;a fi equently determine the species, and that these markings 
ai e lost in the mineralization of the shell ; and when it is also consi- 
dered, that even the forms of the shells are considerably different, at 
different periods of their growth, we must see how difficult it will 
often be to determine whether any specific analogy exist, or not, be- 
tween the recent and the fossil shell. 
Lamarck describes three fossil species : C. pediculus, C. inflata, 
and C. sulcosa, as being found at Grignon. 
I have found several of this genus in the Essex cliff, which I am 
disposed to refer to C. pediculus. The striae must, however, be ac- 
knowledged to be finer and closer than in the recent shell. They 
are perhaps nearer allied to C. costata, Linn. 
The sulcated specimen, Plate V. Fig. 24, from Verona, appears to 
merit, from its size, the being considered as a species distinct from 
an\ at present known. Other species, with a smooth surface, are 
also obtained from the Veronese territory. 
X. Ovula. A tumid univalve, more or less elongated in a point, 
at the ends; the edges involuted, and the opening longitudinal, and 
without teeth on the left side. 
Bruguiere separated from the genus Bulla, of Linnaeus, the Bulla 
ovum, volva, &c. those shells which, having their edges rolled inwards, 
being elongated at their extremities, and not being dentated on their 
left side, seemed to constitute a distinct genus : these he has, there- 
