1904] The Canadian Species of Trocholites. 17 



worth, the Curator of the Cambridge Museum. And, a study of 

 the original types of T. Canadensis and of the similar specimens 

 collected "by Dr. Ami, has necessitated the conclusion that the 

 fossils collected by Dr. Bigsby in 1822 at Montmorency Falls and 

 at Lorette, which Salter referred to '■'• Lituites {Tiocholites) a?n- 

 moneiis''' and Foord to Trocholites planorbifonm's, are also identical 

 with T. Canadensis. 



To test the correctness of this conclusion, two of the best 

 specimens of T. Canadensis that Dr. Ami obtained at the Natural 

 Steps, were sent by the writer early in January last, to Mr. G. F. 

 Crick, of the British Museum (Natural History), for comparison 

 with the presumably similar specimens collected by Dr. Bigsby, 

 in that Museum. In reply to this communication, Mr. Crick thus 

 writes, in a letter dated January 22nd, 1904: " I have carefully 

 examined the specimens in this Museum to which you refer and 

 am quite satisfied that they are specifically identical with the ex- 

 amples of Trocholites Canadensis, Hyatt, that you have sent for 

 comparison. The following particulars about the specimens here 

 may be of interest to you. This Museum contains five examples 

 from Montmorency and two from Lorette, that Dr. Foord (Cat. 

 Fossil Cephal. Brit. Mus., pt. 11, p. 49) referred to Trocholites 

 planorbiformis, Conrad. The two specimens from Lorette (No. 

 26568) were presented to the Museum by Dr. Bigsby. The five 

 Montmorency specimens are among the foreign collections trans- 

 ferred from the Museum of Practical Geology. Four of these 

 (c. 4105, a — d) were presented to that Museum by Dr. Bigsby, 

 but how 'the other specimen (c. 4106) was obtained is unrecorded; 

 it bears an original label ' near Montmorenci Falls, near Que- 

 bec' " In a later letter Mr. Crick adds that it would seem that 

 Dr. Bigsby presented examples of the species both to the British 

 Museum and also to the Museum of Practical Geology in 185 1. 



Professor Hyatt did not state at what particular geological 

 horizon his T. Canadensis occurs. But the limestone at and near 

 Montmorency Falls, and at Lorette, is distinctly stated to be 

 Trenton by Dr. Bigsby in 1853,* and by Dr. R. W. Ells in 1889.! 



* Quart. Journ. Geol. Soc. London, vol. ix, pp. 84—86. 

 + Geol. and Nat. Hist. Surv. Canada, Ann. Rep., N.S., vol. in, pt. 2, 

 pp. 22K, and iqK. 



