312 



edge. The aperture is ovate, indented to the extent of one-third its 

 height on the lower side by the penultimate whorl. Some fragmentary 

 specimens shew that, in the perfect aperture, the lowest lip is much 

 thickened next the umbilicus, and forms a thin layer, on the side of the 

 whorl. The surface is usually obscurely striated, and sometimes irregu- 

 larly undulated in the direction of the striae ; the latter radiate from the 

 umbilicus to the dorsum in a gently sigmoid curve. 



The width, or the diameter transversely through the umbilicus, varies 

 from a little less than one-third to one-half the diameter. 



This species is closely allied to B. acutus, (Sowerby,) but is in general 

 not so much compressed. 



Locality and Formation. Stanbridge, range 6, lot 20 ; Quebec group. 



Collectors. J. Richardson, T. C. Weston. 



CEPHALOPODA. 



ORTHOCEKAS ATTICUS. (N. sp.) 



Description. Shell short, rapidly tapering ; section circular ; septa 

 from six to eight to the inch ; siphuncle about one-seventh the whole 

 diameter, half way between the centre and the margin, not much, if at all, 

 inflated between the septa. Surface unknown. 



The specimen is 4 inches in length ; diameter at the larger extremity, 

 21 lines ; and at the smaller, 7 lines. Diameter of the siphuncle about 2i 

 lines, where the shell is 15 lines. 



Locality and Formation. Corey's farm, lot 7, range 8, Stanbridge, 

 C, 1, section Geol. of Canada, p. 844 ; Quebec group. 



Collectors. Sir W. E. Logan, E, Billings. 



ORTHOCERAS REPENS. (N. sp.) 



Description. Shell small, gradually tapering ; section circular, or 

 nearly so ; siphuncle cylindrical, in contact with the shell ; septa thin, 

 strongly concave, numerous, about eighteen to the inch. Surface un- 

 known. The shell appears to be obscurely annulated. 



A specimen 5 inches in length has a diameter of 9 lines at the larger 

 extremity, and 4 lines at the smaller. The siphuncle is 1J lines in diam- 

 eter, and perfectly cylindrical, exhibiting no trace whatever of inflation 

 between the septa. 



Locality and Formation. Phillipsburg, B 2, section Geol. of Can., 

 p. 844 ; Quebec group. 



Collector. Sir W. E. Logan. 



