346 General Notes. [April,, 



tion in many of the forms, so that these accelerated forms eventu- 

 ally become so much more numerous than the others that the 

 latter are frequently looked upon as missing, although usually to 

 be found if carefully searched for. In addition to this cause, the 

 same effect is increased as spring advances and summer ap- 

 proaches, by the shallow water forms being swept in from the 

 streams and continuing their reproduction in the lake waters. 

 And in the cases where examinations are made from water sup- 

 plies passing through storage reservoirs, the influence of the still 

 water in the reservoir, and of its bottom of sluicy mud, is also to 



be considered. As summer wanes an 



d cold weather again ap- 



proaches, the winter forms increase ii 



1 activity and abundance, 



while summer forms become more in 



active, and the preponder- 



ance is again reversed." 





Under the caption of "A Tumor of the left auricle," D. N. 

 Kinsman, M. D., of Columbus, gives an excellent clinical re- 

 port of a rare and interesting medical case. Though chiefly 

 valuable to physicians, the microscopical portion is sufficiently 

 prominent to justify its appearance in the proceedings. 



The nature of" muscular contractility " is treated at length by 

 Jacob Redding, M. D., of Falmouth, Ind. The author's theory 

 seems to rest partly upon plausible but not altogether safe rea- 

 soning as to what would be likely to be found ; his description of 

 the tissues studied is not likely to be fully accepted by histolo- 

 gists, who will approve still less his free statements as to the su- 

 perficial view of former authors, and of their having completely 

 ignored, or, at least, remained silent upon the subject of the inte- 

 rior of the muscular "cells." The article will repay a careful 

 study. It is illustrated with a diagrammatic plate, which delin- 

 eates with great distinctness the author's theory. 



Shorter articles occur upon the " Innervation of the lungs," by 

 A. M. Bleile, M. D. ; " Gregarina in the American lobster," by 

 Professor A. H. Tuttle, and " Destruction of Acari by a fungus," 

 by C. M. Vorce. Also, a review of different kinds of " Binocular 

 microscopes," by George E. Fell ; an argument in favor of mak- 

 ing " Homogeneous-immersion obiectives adjustable," by George 

 E. Blockhan, M. D., and a description, by E. L. Shurley, M. D ;; 

 of "An improved slide for the examination of gaseous matter. 

 This is a glass slide with an attached cell and cover-glass, the 

 center of the bottom of the cell being raised by a glass disk, so 

 that the bottom of the cell will be within reach of the focal capa- 

 city of the objective used. The gas is introduced through an 

 opening in the side of the cell by means of a fine metallic canula 

 and a small flexible rubber tube, supplied from a compressible 

 rubber bag or globe, such for instance, as in the instruments 

 used in medical practice for the insufflation of powders, or in the 

 chemical laboratory for operating wash-bottles and other appara- 

 tus. The method is capable of further usefulness in microscopy. 



