ELECTROPLAX OF ASTROSCOPUS 107 
Paraffin sections of the electroplaxes (vertical) fixed in pure 
corrosive sublimate were stained for 6 hours in the above mix- 
ture. The results were as follows: The jelly connective tissue 
stained red, the electroplax proper with its three layers stained 
yellow. The rods were scarcely visible, staining the same color 
(yellow) as the electroplax. The fact that the rods stained 
yellow would indicate again that they are composed of muscle 
tissue, and this in connection with the picro-nigrosine stain 
in which the rods stained the same color as muscle gives us 
strong ground for believing that the rods are composed of muscle 
tissue; probably involuntary muscle fibers as the rods are not 
striated. The fact also that the jelly electric tissue stained red 
shows again that it must be of the same composition as ordinary 
white fibrous connective tissue. The controls were the same as” 
those for Van Gieson’s picro-nigrosine. 
It may be objected that the rods did not stain the same color 
as the electroplax proper with Mallory’s connective tissue 
stain. To explain this we may say that the rods stained a 
brilliant red, which is the color that muscle tissue should take 
in the above stain. The fact that only the electroplax stained 
a reddish-purple shows that the rods are more strictly com- 
posed of a muscle substance than the electroplax itself. 
The only tissue now left of which the rods might be com- 
posed is nervous; that is, the rods might be nerve endings of some 
kind, which they resemble a little. In order to test this Paton’s 
silver nitrate stain for demonstrating nerve fibers and endings 
was applied and the results carefully noted. The stain and 
fixation were as follows: | . 
The electric organ was fixed in 10 per cent formalin solution, 
neutralized with magnesium carbonate. It was then cut in small 
strips about 4 mm. thick. These were washed with running 
tap water for 12 hours and then in three changes of distilled 
water for about 30 minutes. The tissue was then put in I per 
cent silver nitrate solution for 6 days in the dark. The tissue 
became a reddish-brown in color. (It may be noted here that 
if the tissue becomes a yellowish-brown the stain has not been 
applied correctly, and it is advisable to throw the whole speci- 
JOURNAL OF MORPHOLOGY, VOL. 26, No. 1 
