2i^4 AMERICAN JOURNAL 



sale reduction. In this European list is placed, by error, " U. 

 depressiis, Lam., North Holland," instead of New Holland, and 

 I have noticed various other small errors of the pen and some of 

 the press, in this magnificent work, but considering the im- 

 mensity of an affair which required the author to consult eleven 

 hundred works in its preparation, he may be congratulated upon 

 having made it so nearly perfect. 



The " Synopsis " will of course become a necessary aid to all 

 collectors and students of the Unionidae, and I hope that the 

 author has had a sufficiently large edition prepared to enable all 

 who desire it to procure copies. The mechanical execution and 

 material of the volume leave nothing to be desired, being even 

 superior in appearance to the usual luxurious style of Dr. Lea's 

 publications. 



Canadian Naturalist. V, No. 1. July 30, 1870. 



Lower Canadian Land and Fresh Water MoUusca. By J. 

 F. Whiteaves. 



Loiver Canadian Marine MoUusca. By the same. 



Two small papers containing additions to lists formerly pub- 

 lished in the "Naturalist." Bythinia tentaculata is found living 

 in Lachine Canal, introduced from Europe probably. 



Proceedings of the California Academy of Sciences. IV. Part 2, 1870. 



071 the Shells of Aritioch, Gal., and vicinity. By H. P. 

 Carlton. 



Shells of Truchee River and vicinity. By H. P. Carlton. 



TJie West Coast Fresh-water Univalves. No. 1. By J. G. 

 Cooper, M. D. 



In this paper the author is even more conservative than in 

 his paper on the terrestrial species, reducing many species to 

 " varieties," and referring many species to eastern North Ame- 

 rican types, although generally recognized as distinct. It would 

 be simply a waste of time to attempt to correct what appear to 

 me to be the very numerous and grave errors of this paper, the 

 author of which seems to have predetermined before studying 

 the species, that too many had been described. Those Avho take 

 a very conservative view of the subject will doubtless be well 

 pleased with the paper, and we recommend it to their perusal. 



Proceedings of the Academy of Natural Sciences of Philadelphia- 

 April, 1870 



