Miscellanies. 395 



January 16, 1839. — Rev. F. W. P. Greenwood, Vice President, in 



the chair. 



Dr. Martin Gay made a report upon some specimens of minerals 

 committed to him, and more particularly upon what is termed Arbo- 

 rescent native Silver. It is usually supposed that minerals assume 

 the arborescent, fibrous form, by a sort of crystallization. But he 

 had been led to suppose that it was produced mechanically, some- 

 thing in the following way : A mass of ore is subjected to heat, suf- 

 ficient to reduce the metal to a semifluid state. This is suddenly 

 cooled, when the whole mass as suddenly contracts, and forces out 

 the metal through the interstices of the matrix in the thread like form 

 in which we find it. Dr. Gay has in his possession a piece of copper 

 ore which he took from a furnace and which afterwards presented 

 upon its surface these so called arborescent crystals. Dr. Gay had 

 not heard the phenomenon accounted for in this way, nor met with 

 any detail of so plausible an explanation in any book. 



Dr. D. H. Storer announced the reception of a collection of fishes 

 from Puerto Cabello, among which were the following genera ; Me- 

 soprion ; Prionotus ; Hemiramphus ; Exocetus ; Clupea ; Caranx ; 

 ChJBtodon and Acanthurus. - 



February 5, 1839.— Geo. B. Emerson, Esq., President, in the chair. 



Dr. D. H. Storer read a letter from J. G. Anthony, Esq., of Cin- 

 cinnati, Ohio, containing the description and figure of a new species 

 of Anculotus, found near that city, to which he gave the name of 

 Anculotus costatus. Also announcing a new species of fossil Caly- 

 mene, and another curious fossil recently discovered by him and 

 about to be published. 



Simon E. Greene, Esq., stated that he had lately seen the Parus 

 Hudsonianus in Brookline, which is much farther south than it has 

 been before noticed. Audubon had seen it in Labrador, and believed 

 that it had been seen in Maine. Nuttall mentions its original discov- 

 ery at Hudson's Bay. 



Dr. T. M. Brewer exhibited the skin of a goose, killed in Boston 

 harbor, and which is rarely seen in this region ; it was the young of 

 the snow goose. 



Dr. J. WvMAN exhibited the head of a young Lemur, {Lemur 

 cotta), from Madagascar — also specimens of " measly pork" in which 

 were vast numbers of parasitic animals, inhabiting the cellular mem- 

 brane ; they did not agree in their characters with the Cysticencus, 

 which is usually described as constituting this disease. 



