Structure and Polarity of Electric Motor Nerve-Cell in Torpedoes. 235 
were less and less. In the central parts of the specimen no osmotic action is 
shown. The osmotic action produced by the alcohol has not moved the 
nuclear organs with reference to one another. In the specimen in question 
the plasmosome is clearly oriented with reference to the dorso-ventral line. 
No matter from which side the nuclear content has been compressed, the 
plasmosome is always clearly ventral in the compressed mass. 
Torpedo ocellata, No. 22, 30 cm. long (large), killed with a knife and the 
entire brain fixed in Carnoy’s fluid; absolute alcohol, chloroform, and glacial 
acetic acid, equal parts, the fluid being saturated with corrosive sublimate. 
This specimen showed about 85 per cent of its plasmosomes oriented ventrally, 
the remaining 15 per cent being scattered in median or somewhat dorsal 
positions. 
Torpedo ocellata, No. 23, 30 em. long (large), killed with knife and brain 
fixed in Carnoy’s fluid; chloroform, absolute alcohol, and acetic acid, no 
sublimate being added. A fair fixation with 90 per cent of the plasmosomes 
ventrally oriented. 
Torpedo ocellata, No. 24, 11 em. long (small). This small fish was thrown 
whole into 60 per cent alcohol, containing 3.5 per cent of formol. It had 
given many shocks before being killed. No orientation in a ventral direction 
beyond a possible 5 per cent was found. 
Torpedo ocellata, No. 25, 38 cm. long (large). This fish was left undisturbed 
in a tank for 48 hours and then gently lifted out on a tray, where it remained 
until dead. The brain was fixed in Bouin’s fluid. 99 per cent of the plas- 
mosomes were oriented sharply in a ventral direction. Chromosome bodies 
were somewhat clumped, owing to the natural death of the fish, the karyosomes 
standing out plainly and staining sharply and differently from the peri- 
chromatin. 
Torpedo marmorata, No. 26,16 cm. long (small). This fish was left undis- 
turbed 48 hours and allowed to die on tray without discharging electricity. 
About 5 per cent of ventral orientation of the plasmosome was found. 
Torpedo marmorata, No. 27, 11 em. long (small). This small fish was 
irritated until considerable electricity had been discharged and then the 
brain-case was cut out while alive, the animal giving off strong shocks. After 
cutting sections the electric motor nerve-cells showed barely 5 per cent of 
ventral orientation, which appears to refute Magini’s theory. 
Torpedo ocellata, No. 28, 16 em. long (small). This fish rested undisturbed 
for 48 hours and was allowed to die on tray. 10 per cent of ventral orientation. 
Torpedo ocellata, No. 29, 11 cm. long (small). Caused to discharge freely 
and then killed by cutting out brain, with consequent strong shocks. No 
perceptible orientation. 
Torpedo ocellata, No. 30, 40 cm. long (large). Kept for 48 hours at rest and 
then gently lifted from the water on a board and allowed to die without giving 
shocks. Brain fixed in Bouin’s fluid. Sections in celloidin and paraffin show 
over 95 per cent of ventral orientation. 
