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NATURAL SCIENCES OP PHILADELPHIA. 49 



February 7th. 

 Mr. Lea, President, in the Chair. 



Forty-nine members present. 



The following were presented for publication : 



" Descriptions of new species of American Fluviatile Gasteropods, 

 by J. G. Anthony." 



" Supplement to a Catalogue of the Venomous Serpents in the 

 Museum of the Academy of Natural Sciences, by E. D. Cope." 



" Catalogue of the Calamarian Serpents in the Museum of the 

 Academy of Natural Sciences, with notes and descriptions, by E. D. 

 Cope." 



Mr. Binney called attention to a species of Leda, presented this evening, 

 which, Dr. Gould states, is common to Japan and Massachusetts. 



A discussion on geographical distribution then took place, in which Dr. 

 Le Conte mentioned that he had prepared a map representing the provinces 

 of geographical distribution of Coleoptera in the territories of the United 

 States ; he divides the temperate part of the continent into three (or perhaps 

 four) districts : 1. Atlantic, extending westwardly to the longitude of the 

 mouth of the Platte ; 2. Central, extending from the mouth of the Platte to 

 the Sierra Nevada ; 3. Pacific, including the water shed of the maritime 

 Pacific coast. These districts are each divided into several provinces, and with 

 larger collections the Central, as at present defined, may be found to be in 

 reality two districts, limited by the Rocky Mountains ; of these the eastern 

 will be called the Central, and the western the Interior district. This map 

 accompanies a memoir on the Coleoptera of Kansas, Nebraska and New Mexico, 

 published in the Smithsonian Contributions to Knowledge. 



Mr. Binney remarked, that having prepared for the Smithsonian Institution 

 a catalogue of the terrestrial and fluviatile Gasteropods of North America, he 

 was able to present the following results : 



Of the boreal regions but little is known. The only data we have are from 

 Greenland. Both the fresh water and land species are peculiar to that country, 

 excepting the European Helix hortevsis, which has been introduced also in 

 Canada and New England. 



Of Mexico also but little is known. A few of its land species are found in 

 Texas ; they are, however, confined to that region, not extending farther north. 

 The genera are more tropical than in the rest of the continent. Fluviatile 

 species are very rare in Mexico, judging from the few data we have. The 

 species appear different from those of the Atlantic region. 



On the west coast the species of land shells are quite distinct from those of 

 the Atlantic region, excepting Bulimus zebra ; the genera, however, are the 

 same, though fewer in number. Among the fluviatile species are found eleven 

 species of Pulmonates, which also inhabit the Atlantic region. 



In the Atlantic region are two or three species of land shells found in 

 Europe, and a few fluviatile Pulmonates. The occurrence of the Asiatic 

 species quoted from the United States may well be doubted. 



The following table shows the facts presented by Mr. Binney. It is neces- 

 sarily imperfect, owing to the small amount of material, the somewhat con- 

 fused synonymy, &c. 



Column 1 contains the species found in the Pacific region. 



Column 2, those of the Atlantic region. 



Column 3, those common to the Pacific and Atlantic region. 



I860.] 4 



