252 



Description. This is a large, elongated, gradually tapering species, 

 with a large lateral siphuncle. A specimen, three feet in length, tapers 

 from a diameter of about four inches at the larger extremity, to one inch 

 at the smaller. The siphuncle in the same length tapers from about six- 

 teen lines to nine lines ; and it is thus more than one-half the whole 

 diameter near the apex, but less than one-third near the chamber of 

 habitation. The section is circular, or nearly so. 



In one specimen, where the diameter is nine lines, there are six septa 

 to one inch in length. In another specimen of a siphuncle, seven inches 

 in length, eleven lines in diameter at the larger and seven at the smaller, 

 there are twenty-three septa. In the large specimen, where the diameter 

 is three inches, there are four septa in fourteen lines. The average 

 appears to be between three and four septa to the inch, from a diameter 

 of two inches and upwards. The detached siphuncles are usually a little 

 flattened on the ventral side along the line of the contact with the shell. 

 Surface unknown. 



Locality and Formation. I, K, L, M, N, Table Head and Point 

 Rich, Newfoundland ; Quebec group. 



Collector. J. Richardson. 



ORTHOCERAS SERVILE. (N. sp.) 



Description. Section ovate, in the proportions of about fifteen to ten. 

 The rate of tapering for the shorter diameter supposed to be the dorso- 

 ventral, is about one line and a half to the inch. The lateral diameter 

 diminishes at the rate of three lines to the inch. Only two of the septa 

 are visible in the specimen ; they are at the larger extremity, and are 

 distant about one line from each other. Surface with fine engirdling 

 striae. Siphuncle unknown. 



Length of the specimen 3 inches ; lateral diameter at the larger ex- 

 tremity 15 lines, at the smaller 6 lines ; dorso-ventral diameter about 10 

 and 4J lines. 



This is a short, compressed, rapidly tapering species, belonging to the 

 theca-shaped group to which 0. hastatum (Black River limestone), and 

 0. xipJiias (Trenton) belong. 



Locality and Formation. L, Point Rich, Newfoundland ; Quebec 

 group. 



Collector. J. Richardson. 



