OF ARTS AND SCIENCES. 89 



The Corresponding Secretary acted as Secretary, and read 

 the record of the proceedings of the last meeting. 



Dr. J. Wyman exhibited to the Academy a dissection of the 

 brain, nerves, and electric organs of the Torpedo occidenialis, 

 Storer, which is occasionally captured at Provincetown, Cape 

 Cod, and adjoining localities, during the month of November. 

 As regards its anatomical structure, it does not differ materially 

 from the European species. Dr. Wyman estimated the num- 

 ber of plates or laminae composing the two batteries at between 

 250,000 and 300,000 ; the number of prisms was about thirty- 

 six to the square inch. He was able to trace the minute 

 structure of the laminae with the microscope, and found 

 the ultimate distribution of the nerves to be the same as de- 

 scribed by Wagner. Each ultimate nerve-fibre on reaching 

 the lamina divides into a series of branches, which unite and 

 form a complete capillary network over the surface of the 

 plate ; but from these branches others are given off, into 

 which the " white substance " of Schwann does not enter. 

 These last branches also divide ; but at the point of divis- 

 ion a large nucleated cell is generally found ; and the fibres 

 proceeding from this terminate in exceedingly slender, mi- 

 nute points, which seem to be lost on the general surface of 

 the plate. 



Professor Horsford read a paper by his pupil, Mr. Dean, em- 

 bodying the results of a series of experiments on the nu- 

 tritive value of various amylaceous articles of food, estimated 

 from the percentage of nitrogen they respectively contain. 

 Some remarks were made upon this by the President and Dr. 

 Gray. 



Professor Horsford also exhibited specimens of the fer- 

 ruginous incrustation of the Cochituate water-pipes, which 

 in some places had occurred to such extent as to diminish 

 their calibre by one sixth, and the flow of water as much as 

 twenty per cent. He thought the incrustation did not proceed 

 now at so large a rate as at first. The President, Mr. Tread-^ 



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