CARBONIFEROUS FOSSILS OF IRELAND. 29 



Macrocheilus ovalis. M'Coy. (PL V. fig. 3). 



Sp. Ch. — Oval; spire short, of three convex whorls; pillar lip flattened; base attenuated; surface smooth. 



This species is allied to the Buccinum imbricatum (Sow,), but is distinguished from it by the shorter spire, 

 the broad, distinctly flattened pillar, and the lengthened, slender base ; the outer lip is entire, thin, and without 

 a notch at tjie base ; the volutions are all convex, with simple sutures. The flattened pillar approximates this 

 curious species to the genus Littorina, but the prolongation of the base of the shell induces me to place it rather 

 in this group ; it is interesting, however, as indicating the passage from one genus to the other. Length ten 

 lines ; width seven lines ; length of the mouth six lines. 



Macrocheilus parallelus. Phil. sp. 



Bucciniun parallele. Phil. Geol. York. 



Sp. Ch. — Elongate, turreted; volutions convex; upper third of each whorl flattened, and finely striated 

 spirally ; lower portion with very coarse, spiral sulci. 



This well marked species occurs but very rarely ; the smallest fragments are easily recognized by the dis- 

 similarity of the upper and lower parts of each whorl. 



Macrocheilus rectilineus. Phil. sp. 



Buccinum rectilineum . Phil. Geol. York. 



The specimens I have seen of this shell only differ from the M. hnhricatus, in having the turns of the 

 spire slightly more tumid, and in the lines of growth being less oblique, and not sinuous. 



Macrocheilus sigmilineus. Phil. sp. 



Bucciniun sigmilineum. Phil. Geol. York. 



Sp. Ch. — Elongate, hemifusold; whorls ventricose; mouth and spire equal in length; outer lip and lines 

 of growth thin, oblique, slightly sigmoid. 



This fine species seems congeneric with the Fusus antiquus of our coasts, which forms the type of the 

 modern genus Chrysodomus. I have only seen a few imperfect specimens. 



Macrocheilus tricinctus. M'-Coy. (PL V. fig. 4). 



Sp. Ch. — Globose; spire very short, acute, of three smooth, convex whorls; body whorl large, tumid, 

 upper half smooth, lower half girt with three strong, spiral sulci. 



This little species is remarkable for the spiral ridges being placed so low down on the basal whorl, that 

 they are cone ealed on the spu-e by the suture, leaving that part of the shell smooth. Length one line ; 

 diameter one line and a quarter. 



Loxonema. Phil. 



Gen. Ch. — Shell spiral, elongate ; mouth elongate, effuse below, right lip thin, wa^■ed ; inner lip obsolete ; 

 no umbilicus ; surface with arched, prominent strias. 



A provisional genus established by Professor Phillips for the reception of those elegant Palseozoic fossils for- 

 merly described as Melania, Turritella, &c. Although the characters of the genus are rather indefinite, yet 

 by its adoption we avoid the serious error of including so many recent genera in the older rocks. It is here 

 considered as a sub-genus oi Macrocheilus. 



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