I 



64 



Peniamerus oUongus, Hall 1843. Geol. Rep. 4th Diatr., N. York, 



p. 7, figs. 1-5. 

 " 1852. Pal. N. Y., vol. II., p. 79, pi. 



25, figs. 1, a-m, and pi. 26, figs. 1, a-d. 



Billings 1863. Geol. Canada, p. 316, fig. 326. 



Dajridson 1867. Brit. Silur. Brach., p. 151 (which 



see for a list of synonyms of British 



and European specimens of this species) 



pi. 18, figs. 1-12 and pi. 19, figs, land 2. 

 " " KichoLson 1875. Rep. Pal. Prov. Ont., p. 61, figs. 



31, a-h. 

 Hall & Whitfield .... 1875. Rep. Geol. Surv. Ohio, vol. II., 



pt. 2, p. 137, pi. 7, fig. 9. 

 Whitfield 1882. In Geol. Wiscons., vol. IV., p. 



288, pi. 17, figs. 4-9. 



Durham, J. Townsend, 1878-82 : four casts of the interior of the shell. 



This well-known species, which is stated by Hall to be abundant in 

 the Clinton group of the state of New York, appears to be compara- 

 tively rare in the Clinton and Guelph formations in Canada, but to be 

 one of the commonest fossils of the Niagara formation throughout 

 Ontario, and of the two upper divisions of the Anticosti group of the 

 island of that name. It has long been known to be abundant in the 

 outlier of Niagara limestone at Lake Temiscaming, and, more recently, 

 it has been recorded by Dr. H. M. Ami,* as occurring at the Forks of 

 the Scaumenac River, in the province of Quebec, where it was collected 

 by Dr. R. W. Ells in 1883. 



Pentameeus oblongus, var. bisindatds. 



PentamerusbisinvMtuSf^cChesaey 1861. New Pal. Foss., Extr. No. 2, 



p. 85. 



1865. lUustr. N. Sp. Foss., pi. 9, figs. 



1, a-b. 



Whitfield 1882. Geol. Wiscons., vol. IV., p. 290, 



pi. 17, fig. 3. 

 Peiitamerus oblongus, yai. hisinuatiis, 'Rail. .IS9Z. Pal. N. Y., vol. VIII., pt. 2, 



fasc. 2, pp. 238 and 239. 



Durham, J. Townsend, 1882 : a cast of the interior of the dorsal or 

 brachial valve, showing the single septum said to be characteristic of that 

 valve of P. bisinuatus. But, according to Hall (op. cit.), the septa of the 

 brachial valve of P. oUongus " are usually very short and rest upon the 

 inner surface of the shell. It sometimes happens that these septa unite 

 before reaching the inner surface, and the spondylium thus formed is 

 supported by a very low axial septum. This is the case in the original 

 specimen of P. bisinuatus, McChesney, and in the Wisconsin shell re- 

 ferred to that variety by Whitfield." 



*In Geological Survey of Canada, Report of Progress for 1882-83-84, p. 26 E. 



