170 



August 19, 1846. 



C. T. Jackson, Vice President, in the Chair. 



Dr. D. H. Storer observed that a recent visit to ]\Iartha*s 

 Vineyard had enabled him to collect numerous ichthyologi- 

 cal facts of considerable interest. 



In his Report on the Fishes of Massachusetts, he had stated, upon 

 the authority of Dr. Yale, that a sting-ray was common at Holmes 

 Hole. He had now had the opportunity of seeing both a male 

 and a female specimen, and ascertained it to be Trygon hastata. 



Previous to his visit to Martha's Vineyard, he had not known 

 that Torpedo occidentalis occurred on the coast of Massachusetts, 

 except on the inner or bay side of Cape Cod, from Provincetown 

 to Wellfleet, but while at Chilmark he had learned that it was 

 taken every year at that place, as many as fifteen or twenty indi- 

 viduals being captured in the spring months, in seines and by 

 hook and line. 



Dr. C. T. Jackson read the results of a chemical analysis 

 of Sand from the desert of Sahara, taken from specimens in 

 the Society's cabinet, viz. : 



Organic matter and water, .... 2.30 



Insoluble silicious matter, . . . 91.30 



Perox. Iron and alumina, .... 2.68 



Carbonate of Lime, .... 3. 70 



99.98 

 The Insoluble silicious matter attacked by fusion with Carbo- 

 nate of soda, and analyzed, yielded 



Silex, 84.7 



Alumina and Perox. Iron, . . . 3.0 



Dr. Gould continued his descriptions of new Shells, col- 

 lected by tlie United States Exploring Expedition, and be- 

 longing to the genus Helix. 



