﻿MACROCHILINA. 167 



of the spire, measuring somewhat more than half the height of the shell and 

 rounding rapidly in to form its base. Surface smooth or only marked by 

 indistinct growth-lines. Shell-structure rather thin. 



Size. — Height about 30 mm., width about 25 mm. 



Localities. — From Wolborough there are three specimens in Mr. Vicary's 

 Collection, and one in the Museum of Practical Geology; and from Lummaton 

 there is a specimen in my Collection. 



Remarks. — These fossils appear to Mr. Roberts and myself to agree accurately 

 with one of the figures (194 6) which Phillips gives of his so-called Macrochilus 

 imbricatus, Sowerby, but not with Sowerby's original species. The only difference 

 is that in Phillips's figure the sutures are rather deeper and the mouth is more 

 perfect than in our specimens. The former difference may be due to his shell 

 being in the condition of a cast, or slightly injured round the suture, as is, in fact, 

 my specimen from Lummaton. There can, however, be no question about the 

 identity of these shells. 



But under the head of M. imbricatus, Sow., Phillips figures two shells which, as 

 he himself suggests, belong evidently to two distinct species, and of which, more- 

 over, neither belongs to the Buccinum imbricatum of Sowerby. His smaller figure 

 is a very different shell, which is more elongate, and has a much larger body- whorl ; 

 but his larger figure evidently, as we have just seen, belongs to the present 

 species, and this he also doubtfully refers to the Buccinum acutum of Sowerby. 



Affinities. — This species differs from all the other species that accompany it by 

 being shorter, and by having a shorter and more convex body-whorl. 



It is something like Ampu llaria nobilis, Sow., 1 of the Carboniferous Limestone, 

 but is a wider and smaller shell, and has not the prominent growth-ridges seen in 

 that form. 



6. Macrochilina ventkicosa, Goldfuss, sp. PI. XVII, figs. 8, 8 a, 9. 



? 1844. Phasianella ventbicosa, Goldfuss. Petref. Germ., vol. iii, p. 113, 



pi. cxcviii, fig. 14. 



Description. — Shell rather large, fusiform, somewhat elongate, of six or seven 

 volutions. Apex acuminate. Spire elongate, nearly half the height of shell, 

 consisting of whorls which increase in a progressive proportion, so that the sides 

 of the spire are somewhat concave. Suture linear, almost invisible. Whorls 

 strongly adpressed along the suture, otherwise moderately convex. Body-whorl 

 short, wide, convex, curving rapidly in round the base. Columella short, straight, 



1 1826, Sowerby, ' Min. Conch.,' p. 39, pi. dxxii, fig. 1. 



