100 WINCHELL AND MARCY ON FOSSILS FROM THE 



They are, however, quite distinct specifically from anything at present known to us in the 

 upper silurian. 



Loxonema sululata Conrad (Murchismria sululata Hall). No decisive characters separate our 

 forms from the above species of the Clinton group. The number of volutions is nine or 

 ten. Indications of sigmoid incremental lines, without the faintest trace of a peripheral 

 band or apertural slit, induce us to refer our specimens to Loxonema, as was originally done 

 by Conrad with the New York specimens. It differs from its foreign analogue, Loxonema, 

 sinuosa Sowerby, by feebler transverse striae and a deeper suture, distinguishing it from 

 Holopella. This species is quoted from the Niagara group of Canada West. Geol. of Canada, 

 p. 326. 



SUBULITES Conrad. 



Subulites brevis W. and M. 



Plate II. figure 19. 



A species apparently referable to this genus is evidently distinct from any known form 

 belonging to this age. Aperture unknown ; number of whorls at least five or six, rather 

 rapidly tapering, flattened on the exterior, widely overlapping, attenuated to a sharp edge 

 on the upper side, producing a shallow linear suture which is also very oblique. Transverse 

 section of whorl narrowly crescentic. No surface characters imprinted upon the casts. 

 This species, in robustness and number of whorls, is intermediate between S. elongatus and 

 S. ventricosus. The apical portion in all of our numerous specimens is distinctly bent to 

 one side. 



BELLEKOPHON Montfort. BUCANIA Hall. 



Bellerophon (Bucania) perforatus W. and M. 



Plate III. figure 7. 



Shell large, sub-discoid, with about four whorls moderately impressed, and an umbilical 

 cavity exposing all the volutions. Aperture suddenly and broadly expanded, with the lip 

 almost reflexed. Transverse section of whorl circular, with an indentation on the ventral 

 side. Dorsum of last whorl with a low carina on which are elevated a series of elongated 

 nodes becoming somewhat continuous near the aperture the length of the nodes gener- 

 ally about equal to the distance between them. These are visible on the cast, which also 

 imperfectly preserves some longitudinal markings. The latter, near the aperture, are raised 

 bands with intervening spaces of equal width, and some indications of a general longitudi- 

 nally striated surface. No nodes exist on the young shell. Exterior of shell marked by 

 numerous sharp, abruptly raised longitudinal ridges, which increase rapidly by implant- 

 ation in the vicinity of the trumpet-shaped aperture. The nodes of the shell appear, near 

 the aperture, to have been completely perforated, a circumstance which seems to be 

 only an exaggerated condition of the nodes, as the latter are but apertural modifications 

 of the continuous carina. 



Transverse diameter of aperture at least 2.56 inches ; transverse diameter of whorl, one 

 third of an inch back from the margin of the aperture, 1.58 inch. one inch back, 1.42 

 inch. 



This may be the Bucaiw pervoluta, McChesney, though that is described as below medium 



