each produced into a longer or shorter canal: the inner or columellar lip is smooth, without teeth 

 or crenulation ; a fold or pliciform tooth is, however, observable in several species both at the 

 upper and lower ends of this lip: the outer lip is very seldom thin and sharp-edged; it is gene- 

 rally thickened and involute, frequently quite smooth, sometimes crenulated or denticulated. 

 In their young state the outer lip is thin and sharp-edged, and the outside is not covered with the 

 shining enamel-like shelly coat. 



Since the publication of Lamarck's Hist. Nat des Anim. sans vert, (when only two were 

 known), there have been considerable additions to the number of fossil species, several small 

 species having occurred in the Crag, in the Calcaire Grossier and in the contemporaneous forma- 

 tions, near Bordeaux, in Touraine, at Piacenza, and in Britain;* I believe the fossil Ovula have 

 not occurred in any bed below the London clay. 



I had prepared the above observations on the genus Ovulum, when I was favoured by the 

 Rev. Dr. Goodall with the following extract from the Zoological part of the Voyage de Freyci- 

 net, by M. M. Quoy et Gaimard, which proves the correctness of my suggestion relative to the 

 animal of Ovulum. I am not, however, induced to degrade it from the rank of a genus, because 

 I think there are sufficient distinguishing characters. 



" L'animal de l'Ovule a la plus grande ressemblance avec celui de la Cypree, comme 

 " pouvoit le faire pressentir le grand rapprochement des coquilles. Sa forme gene rale est tout 

 " a fait la meme; son manteau est double; les cirres de la bande marginale, pedicules et renfles 

 " en champignon a l'extremite, sont moins nombreux et ont une autre forme que ceux des 

 " Cyprees. En avant et en arriere les deux lobes du manteau se continuent sous forme de canal, 

 " plus marque en avant, ou il presente un rudiment de tube. Le pied est celui d'une Cypree, 

 " c'est a dire, fort grand, ovale, a bords minces, l'anterieur traverse par un sillon marginal. II 

 " presentoit vers le milieu de cette extremite une sorte de ventouse assez profonde, a bords assez 

 " reguliers; mais n'ayant vu qu'un individu d'Ovule, nous n'osons conclure que ce soit une dis- 

 " position normale. Meme identite pour la tete et la trompe qui paroit pouvoir se dilater en 

 " trompette; les yeux sont seulement un peu plus petits. II existe un rudiment de dent labiale 

 " superieure, foil etroite, en fer a cheval et colleealapeau de maniere a, n'avoir pas une grande 

 " action. La masse linguale, epaisse, ovale, en partie libre dans la cavite buccale, est armee 

 " de petits crochets comme a 1 'ordinaire. L'anus est a l'extremite d'un petit tube flottant dirige 

 " en arriere dans la cavite branchiale; celui-ci est immense et contient deux brancliies, dont 

 " l'une fort grande, en fer a cheval, enferme la plus petite dans son ouverture, qui est dirigee en 

 " avant. L'oviduc, termine par un tube libre flottant dans la cavite branchiale, est dirige 

 " d'avant en arriere. Ainsi, la consideration de 1 'animal de l'Ovule exige presque la reunion 

 " de ce genre avec celui des Cyprees." p.p. 444, 445. 



The following table must be considered as entirely artificial, it is prepared with a view to 

 assist in the ascertaining the names of species, not as an attempt at a natural arrangement of 

 the genus. 



* A large fossil shell having the form of Cyprasa Mus, has been discovered in Holland, and referred to this genus by M. Duclos, under 

 the specific name of 0. tuberculosa ; this shell is, however, more properly arranged with the Cypres. 



