1915] The Ottawa Naturalist. 51 



CONCHOLOGICAL NOTES. 



But few mussels have been recorded from the Hudson Bay- 

 drainage area of Ontario, though many must occur. 



Mr. J. B. Tyrrell, who explored the District of Patricia in 

 1913, found Unio (Lampsilis) luteolus in the Fawn and Severn 

 about lat. 54° N. The species doubtless extends down to Hud- 

 son Bay as it does down the Mackenzie. The shells are smaller 

 and lighter in color than these of the same species from the 

 Rideau river and the Rideau canal. In the latter between 

 Bank and Concession Streets, Ottawa, they are ordinarily of 

 large size, green in color, and beautifully rayed. The Patricia 

 shells resemble closely the L. luteola found in Lake Nipissing at 

 North Bay, and in Lake Talon, near Rutherglen, but are 

 not as yellow on the same species from Lake Gauvreau in the 

 Gatineau hills. 



No mussel peculiar to America has a wider range than this. 

 It is found from the Brazos of Texas to the Arctic Circle and 

 from the Rocky Mountains to the St. Lawrence and the Hudson 

 drainage areas. Throughout this vast extent, under conditions 

 varying from crystal lakes and streams to muddy sloughs and 

 pools, in polar cold and torrid heat, it preserves unvaried the 

 pecuhar undulations of the beaks which distinguish it from 

 alhed species. It thus affords a striking proof of the proposi- 

 tion of Quatrefages, that specific characteristics — properly so- 

 called — are not permanently affected by environment. 



An Anodonta found by Mr. Tyrrell in the Fawn river has 

 the beaks so eroded that it cannot be identified. It is not im- 

 probably A. kennicottii Lea, which was described from Lake 

 Winnipeg and Great Slave lake. 



Another lot of mussels from Northern Ontario was collected 

 in 1914 by Mr. J. K. Latchford in the Missinaibi, where on its 

 way to Hudson Bay it flows under the National Transconti- 

 nental Railway, about twenty miles east of Hearst. They are 

 mainly L. luteola, but include two Anodontae which may be 

 undescribed. Throughout Ontario, especially northward, the 

 Anodontae, or paper-shell mussels, abound. It is seldom, how- 

 ever, that any but mature specimens are collected. The beaks of 

 old shells are nearly so always eroded that positive identification 

 is extremely difficult, except in the case of a few species with 

 prominent characteristics. The result outside of narrow limits 

 is absolute confusion. It is safe to say the only thin-shelled 

 mussels found near Ottawa which can be identified with any 

 certainty are A. (Strophitus) edentula Say A. cataracta Say (= 

 ftuviatilis Dillw. of our lists) and A. subcylindracea Lea. Many 



