234 Papers from the Department of Marine Biology. 



Torpedo ocellata, No. 12, 30 cm. long (large), killed with knife; strong shocks. 

 Neurosomes light yellow. In the prepared sections only about 25 per cent of 

 the plasmosomes were oriented ventrally. Plasmosomes of usual size and but 

 few cases of multiple plasmosomes. 



Torpedo ocellata, No. 13, 35 cm. long (large), killed by cutting out brain; 

 shocks. An evident cross between ocellata and marmorata, which often occurs. 

 White spots with blue centers missing and the marbled markings of marmorata, 

 No experiments. In the prepared sections the plasmosomes were 95 per cent 

 oriented against the ventral wall of the nucleus. The plasmosomes in most 

 cases did not quite touch the membrane. A single normal-sized plasmosome 

 was present in practically all cases. 



Torpedo ocellata, No. 14, 30 cm. long (large), killed with knife; many shocks, 

 no experiments. In the preparations the plasmosome was single and only 

 about 30 per cent were oriented ventrally. A rather smaller size of plasmo- 

 some appeared to be due to fixation or to the alcohols. 



Torpedo ocellata, No. 15, 38 cm. long (large), killed with knife; many shocks. 

 Plasmosomes show a decided and almost perfect ventral orientation. Very 

 few exceptions. One or two plasmosomes displaced by knife, very easily 

 diagnosed. Plasmosomes touch or nearly touch nuclear membrane. Varia- 

 tion of line of orientation from ventro-dorsal line amounts to less than 15. 

 Plasmosome almost always single. 



Torpedo marmorata, No. 16, 42 cm. long (large), killed with knife; few shocks. 

 Plasmosomes show a perfect ventral orientation against wall of nucleus. 

 Variation of line of orientation from dorso-ventral line seldom more than 10, 

 except on dorsal edge, where a few exceptions occur. The remote cells with 

 neurites leaving on other than the ventral edge were carefully examined and 

 it was seen that the plasmosome does not move to the side of the nucleus next 

 to the neurite. 



Torpedo ocellata, No. 17, 32 cm. long (large). This fish was killed by placing 

 in a large dish and inverting a box over this, so that the vapor from a sponge 

 saturated with chloroform would pass into the water and thus into the fish's 

 circulation. Later the box was removed and water that had been saturated 

 with chloroform vapor was added until the fish was dead. When muscular 

 action had stopped, and just before death, the fish began to give a succession 

 of single shocks spaced in such a way as to lead one to think that each was 

 synchronous with a single heart-beat. In the preparations 85 per cent of the 

 plasmosomes were oriented ventrally. A single plasmosome was the rule. 



Torpedo ocellata, No. 18, 30 cm. long (medium), killed with the knife; 

 worried before killing, so that many shocks were given off. Electric lobe fixed 

 in Bouin's and Flemming's fluid. 90 per cent of the plasmosomes were found 

 to be ventrally oriented. Plasmosome single. 



Torpedo ocellata, No. 19, 34 cm. long (large) ; allowed to die in an undisturbed 

 condition in air; back uppermost, no shocks perceived. Died in about 10 

 hours. Orientation of plasmosome not definite, but estimated at something 

 over 10 per cent. 



Torpedo ocellata, No. 20, 37 cm. long (large), killed with knife; brain centri- 

 fuged in skull for 30 minutes, at 2,000 revolutions per minute, 14 cm. radius. 

 Force applied from ventral toward dorsal surface. Fixed in Bouin, pure 

 sublimate-acetic, and Flemming's fluid. 



Torpedo ocellata, No. 21, 35 cm. long (large), killed with knife; shocks. 

 Brain in 96 per cent alcohol. All cells nearest the periphery, where the 

 osmotic action was first and strongest, show a removal of the nuclear content 

 toward a central point. As one examines the cells that occur successively 

 inside or central of this, it may be noticed that the results of osmotic action 



