116 GASTEROPODA OF THE INFERIOR OOLITE. 



34. Alaeia hamus, Desl., var. Phillipsii, D'Orbigny, 1850. Plate IV, figs. 8 a, 



8 b, 8 c. 



1829. Rostellabia composita, Sow. Phillips, G. T., pp. 124, 129, 165, pi. ix, 



fig. 28. 

 1850. Pteroceea Phillipsii, D'Orbigny. Prod., i, p. 270. 



1853. Alaeia Phillipsii, If Orb. Morris and Lycett, Great-Ool. Moll., p. Ill, 



pi. xv, figs. 15, 15 a. 



1854. — — — Morris, Catalogue, p. 234. 



1867. — — If Orb = Al. hamus, Desl. Laube, Ga&t. von Balin, 



p. 23. 



1884. — hamus, Desl., var. Phillipsii, D'Orb. Hudleston, Geol. Mag., 



dec. iii, vol. i, p. 145, 

 pi. vi, figs. 3 and 4. 



Bibliography, &c. — It is noticeable that Morris regarded Al. hamus as a species of 

 the Great Oolite only, and Al. Phillipsii as a species confined to the Inferior Oolite 

 in England (Scarborough Limestone, &c). It has already been shown that Morris 

 and Lycett were incorrect in their identification of Deslongchamps' species, which 

 can scarcely be said to occur in the Great Oolite in England. But it is evident 

 that Morris, judging from the localities quoted in his " Catalogue, " regarded Al. 

 Phillipsii and the true Al. hamus as the same species. Laube takes the same view, 

 but gives no figure. 



If we could obtain perfect specimens of each, the point might be settled. Up 

 to the present time I have never seen a Yorkshire specimen with the wing-digita- 

 tion preserved. In fact I have never seen from any locality in England a specimen 

 of the variety Phillipsii with the digitation. 



Lately an unusually good specimen (fig. 8 a) was obtained from the Scarborough 

 Limestone. 



Description. — The points in which this differs from the Dorsetshire Al. hamus 

 are that the spire is more slender, the costulse are smaller, and the whorls are less 

 boldly muricated ; the aperture is subtriangular as in Al. hamus, and I think there 

 are traces of the spinous swellings on the upper keel of the body-whorl. Imperfect 

 specimens from the Dogger (fig. 8 b) and from the Millipore-bed (fig. 8 c) seem to 

 bear out this view. 



Relations and Distribution. — But little more need be said about the relations of 

 this very doubtful species or variety. Most specimens of Alaria from the Inferior 

 Oolite, which possess a moderately thin spire with longitudinal costulas arranged 

 in a circlet anteriorly on the whorls, and a plain bicarinate body-whorl are likely 

 to be thus referred. The type is a very general one throughout the Oolites, and 



