236 PROCEEDINGS OF THE AMERICAN ACADEMY 



through the telegraphic circuit between Washington and St. 

 Louis, seventeen hundred miles in length. His experiments 

 gave a velocity of a little less than ten thousand miles a 

 second. This result he proposes to test by further experi- 

 ments on telegraphic lines, in which chemical changes of 

 colors are used, instead of markings made by an electro-mag- 

 net. Mr. Walker found that pauses and syllables could be 

 simultaneously transmitted in opposite directions, without in- 

 terference, in the telegraphic circuit, in the same manner as 

 they are in air. 



Professor Agassiz stated that he had ascertained that there 

 are certain animals, capable of performing all the great func- 

 tions of animal life, which consist entirely of cells. He re- 

 ferred, in illustration of his remark, to the genus Coryne of 

 the Polypoid Medusas, found in Boston harbor. He distin- 

 guished the cells of which the tentacles of these animals are 

 composed into three kinds, — epithelian. lasso, and locomotive 

 cells. The tentacles, which consist of two cylindrical bodies, 

 one within the other, tapering to a point, and without any 

 cavities, are composed entirely of such cells. The epithelian 

 cells cover the whole surface of the tentacles. The individ- 

 ual lasso cells throwing out their inner cylindrical body, the 

 tentacles are converted into stems, with long, lateral threads, 

 for catching small animals. By the contraction of their inner 

 or locomotive cells, they are reduced to one tenth of the length 

 they have when elongated. The locomotive cells were stated 

 by Professor Agassiz to undergo endosmosis and exosmosis, 

 accompanied by a change of form in the individual cells 

 which constitute the inner cylinder of the tentacle, and in 

 that change, to become organs of locomotion. The apparent 

 fibres, described by some writers, were said by Professor 

 Agassiz to be merely elongated cells. 



Professor Peirce and Dr. Walter Channing made some fur- 

 ther remarks in regard to the cause of the elongation of the 

 cells. 



After a discussion of considerable length, in which Mr. 



