﻿CAPULUS. 219 



Description. — Shell large, depressed, wide. Spire free (?), much incurved, 

 tending slightly upwards, consisting of rather more than a volution. Apex 

 unseen, but not far from the inner side of mouth. Body-whorl more or less 

 subcircular in section, being flattened or slightly concave above, convex on the 

 back, and more or less produced below, sometimes so as to form a concave wing; 

 horizontally much arched, and divided by five or six indistinct and irregular 

 spiral ridges and furrows, which give it a slightly angulated appearance. Mouth 

 very large. Peristome deeply sinuous or undulating. Surface covered with fine, 

 sharp, irregularly undulating strias, crossed by occasional spiral inequalities. 



Size. — Width about 45 mm., depth about 27 mm., height about 33 mm. 



Localities. — From Wolborough there are two specimens in the Museum of 

 Practical Geology, and three in Mr. Vicary's Collection. From Lummaton there 

 are four specimens in my Collection, one in the Woodwardian Museum, and one 

 in the Lee Collection in the British Museum. 



Remarks. — Though as usual in this genus almost every specimen of the 

 present species has a slightly different shape, there is a general resemblance 

 in them which affords reason for grouping them together, and for distinguishing 

 them from the adjoining species. Their most striking features are the indistinct 

 horizontal furrows and ridges which are seen in very few of the other forms, 

 while in the present species these are much less definite than in G. multiplicatus, 

 Giebel. Other distinguishing points are the incurved and apparently free 

 spire, slightly curving upward, but not distant from the plane of the mouth, 

 and partly overhanging its inner margin ; the boldly undulating peristome, and 

 especially the expansion of the lower part of the body-whorl near the mouth, 

 which thereby sometimes forms an area which is called by Phillips "a wing." 



One of the specimens in the Museum of Practical Geology is the original of 

 one of Phillips's figures of Acroculia vetusta, ' Pal. Foss.,' pi. xxxvi, fig. 169 b. As 

 will be seen by the figure which I have given of it, Phillips's drawing does not 

 quite represent its true shape. It is a somewhat flatter shell than our other 

 specimens, and the " wing " is more extended ; but it is quite possible from its 

 appearance that it has been subjected to pressure, and to this cause the existence 

 of the so-called " wing" may be partially due. 



A comparison with Sowerby's original figure and with Carboniferous specimens 

 of Pileopsis vetusta, Sow., in the Museum of Practical Geology, leads to the 

 conclusion that our Devonshire fossil cannot belong to that species, which is a 

 more limpet-shaped form with less arching whorls and smaller and less recurved 

 spire. The two other figures given by Phillips in the ' Pal. Foss.' do not appear 

 to belong to either of these species, but I have been unable to find the original 

 specimen or specimens from which they were taken, and therefore it is difficult 

 to feel certain on the point. 



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