PROCEEDINGS. 33 



experiments in fish culture, illustrating his remarks by apparatus in 

 which the eggs of the shad, Clupea sapidissima, were in process of 

 hatching. He announced that he had succeeded in keeping shad 

 eggs for twenty-four hours in a half dry condition in moist cloth, 

 and in thus transporting them from place to place, instead of the 

 old cumbersome vessels filled with water. * 



Mr. John A. Ryder exhibited, under the microscope, eggs of the 

 shad in various stages of development, and announced the discov- 

 ery of teeth in shad four or five days old. f 



Sixteenth Meeting, October 28, 1881. 



The President occupied the chair. Thirty-two members were 

 present. 



This evening the Society met for the first time in the Archive 

 Room of the National Museum. Prof. Lester F. Ward exhibited a 

 supposed petrifaction, resembling the hand of a mammal, from near 

 Granger's Station, Wyoming. A discussion followed upon the phe- 

 nomena of opalization, and the formation of pseudomorphs, in 

 which Messrs. Taylor, Gill, Schaeffer, Dall, and Ulke participated. 

 Mr. Henry W. Elliott read a paper On the Habits of the Sea 

 Otter, (Pusa lutris,) of the Northwest Coast, illustrating his 

 remarks by specimens and sketches on the blackboard. % 



Dr. Thomas Taylor exhibited a new form of freezing microtome, 

 invented by himself, and demonstrated its manner of working. § 



Seventeenth Meeting, November 11, 1881. 



The President occupied the chair. Twenty-eight members were 

 present. 



*See Report of the U. S. Commission of Fisheries for 1S81, (Part VIII,) 

 and Transactions of the American Fish Cultural Association for 1882. 



-j-1882. Ryder, John A. The Protozoa and Protophytes considered as the 

 primary or indirect source of the food of fishes. <^Bull., U. S. Fish Cornm., I, 

 1882, pp. 236-251. (Eggs and food of young shad, pp. 248-9.) 



% To be printed in the forthcoming Census report on the Fisheries of the 

 United States. 



§1882. Taylor, Thomas. On a new form of freezing microtome. <Troc. 

 Amcr. Assoc. Adv. Sci., XXX, (Cincinnati Meeting,) 1881, p. 119. 



3 



