66 JOURNAL OF THE [July, 



known and elegant writer, of a great number of little toads leaving the water and drop- 

 ping their tails on the ground ! He drewupon his imagination, not his observation. In 

 April, 1861, I contributed to The Rutgers College Quarterly a paper, under the title 

 " Crangasides : A Batrachian Biograpby." In that paper was shown the use of the tail 

 as pabulum to the frog during a few days at the beginning of a critical change in life, 

 this appendage being absorbed into the animal as condensed alimentation. 



NERVES AND NERVE ACTION. 



BY CARL HEITZMANN, M.D. 

 iRend February ■^d, 1893.) 



'When, twenty years ago, I made the discovery that so-called 

 protoplasm, at that time considered as the living matter', was of 

 a highly complex structure, being traversed by a delicate reti- 

 culum, the points of intersection of which were the nucleus and 

 the granules, my assertion met with incredulity and scorn. By 

 and by histologists satisfied themselves that I was right. 

 Even the French now admit the presence of such a reticu- 

 lum, dubbing it "hyaloplasma." All doubts must vanish upon 

 looking at the photomicrograph published by S. Strieker, of 

 Vienna, in 1890, taken by means of electric light with a 

 power of 2,500 diameters. The photograph, which I here 

 exhibit, is that of a living, or fresh, colorless blood corpuscle 

 of a newt, Proteus, from the Adelsberg grotto in Austria. 

 The reticulum is exactly of the appearance which I described 

 and illustrated in 1873. Since I saw the reticulum in con- 

 tinuous movement during the life of a protoplasmic lump, my 

 conclusion was that the reticulum is made up of the living or 

 contractile matter proper ; whereas the meshes contained a liquid, 

 as such destitute of properties of life, filling the meshes of the 

 sponge-like structure, and permitting the contraction of the solid 

 portions — /.^., the living matter. The contractions consisted in 

 a narrowing of the meshes, an increase of the size of the points of 

 intersection, the so-called granules, and a shortening of the con- 

 necting threads. The extension, on the contrary, proved to be a 

 widening of the meshes, a decrease in the size of the granules, and 

 an elongation of the threads. The protoplasmic lump being en- 

 sheathed by an extremely thin layer of the same substance that 

 builds up the reticulum and the meshes, the fluid filling the 



