WHITEAVE8.] CRETAOEOtIS FOSSILS, NORTH WEST TERRITORY. 16Y 



Two well preserved moulds of the exterior of the left valve, one 

 nearly perfect and both shewing the surface mai-kings well ; three oasts 

 of the interior of the same valve, and three imperfect right valves. 



It is not improbable that specimens of an Oxytoma from Subdivisions 

 C and B. of the Cretaceous rocks of the Queen Charlotte Islands, 

 which the writer referred to the 0. macronata of Meek and Hayden 

 (on pages 238 and 251 of the first volume of Canadian " Mesozoic 

 Fossils ") may prove to be immature individuals of the present species. 



Inoceramus. 



Three casts of the interior of detached valves of shells which obvi- 

 ously belong to this genus, but which are far too imperfect and too 

 badly preserved to be determined specifically. They seem, however, 

 to represent two species, both of which are referable to the section or 

 subgenus OatiUus of Brongniart, in which the hinge line is elongated 

 in a direction parallel with the longer axis of the shell. 



Trigonoaroa tumida, Whiteaves. 



Trigonoarca tumida, Whiteaves. 1884. Geo!, and Nat. Hist Surv. Can., Mesoz. 

 Foss., vol. I., p. 235, pi. 31, fig. 6. 



One imperfect and and badly preserved cast of the interior of both 

 valves, and three similar casts of detached left valves, which resemble 

 the type of this species very closely in external form, but which are in 

 too bad condition to be identified with much certainty. 



Trigonia Dawsoni, Whiteaves. 



Trigonia Dawsoni, Whiteaves. 1878. Geol. Surv. Can., Eep. Prog. 1876-77, p. 

 154. 1884. Geol. and Nat. Hist. Surv. Can., Mesoz. Foss., 

 vol. I., p. 231, pi. 31, figs. 1 and la. 



A few specimens, which are evidently conspecific with the original 

 types of T. Dawsoni fi'om the Iltasyouco River and Sigutlat Lake. 



In 1884 the writer expressed the opinion that the shells for which 

 this name had been suggested were probably identical with the Trigonia 

 intermedia of Fahrenkohl, from the Neocomian of Eussia. About a 

 year after this statement was made, however, three unusually large, 

 perfect and well preserved specimens of T. Dawsoni from Skidegate 

 Inlet in the Queen Charlotte Islands, were presented to the Museum 

 — Z 



^'^ June, 1889. 



