226 Papers from the Department of Marine Biology. 



paratively small proportion of the nerve-cells in a given electric lobe, 

 and this proportion appeared to vary in a number of counts that were 

 made from as much as 35 per cent to as low as practically nothing. 

 It seems that the smaller fish had the larger proportion and also that 

 the presence of this body was in some way related to the fish that had 

 the plasmosome distributed in several bodies, some of which were small. 



This telonucleolus appears as a hollow sphere, often larger than the 

 largest plasmosome and seldom smaller. Its wall is composed of a 

 clear, sharply defined membrane that is less stainable than any other 

 material in the nucleus, even refusing to become colored with such 

 counterstains as eosin and erythrosin, or para-carmine and hemalum. 

 It is also refrangent, and this property makes it easy to see at once when 

 it is present in a cell. I have not measured its refrangency as compared 

 with other structures in the cell. 



The thickness of its wall is inconsiderable, but could be accurately 

 measured. This wall was continuous and appeared to be more or less 

 impermeable to most liquids, because the only cases in which the sphere 

 appeared to collapse were when it was cut by the knife in sectioning. 

 It appeared to collapse and crumple quite completely, showing that its 

 walls were either very thin or that they had very little rigidity. 



The content of this telonucleolus appeared to be a fluid, and a very 

 slight and non-stainable reticulum of "linin." Besides these, in prac- 

 tically all cases it also contained a very small plasmosome which was 

 in no way different from the other plasmosome bodies in the nucleus. 

 This contained plasmosome was usually so small, however, that it had 

 only one or two of the plasmosome vacuoles and the inner, darker- 

 staining layer of the refractive shell did not appear to be developed. 

 As the same is true, however, for plasmosomes of this small size that 

 are found outside of the telonucleolus, it is safe to say that all the plas- 

 mosome bodies in the nucleus possess the same kind of structures, 

 whether within or without the telonucleolus. 



The position of the telonucleolus is peculiar and has some unknown 

 significance. It is always found close to or touching one of the plasmo- 

 somes, large or small; further, the little plasmosome inside of it is also 

 oriented in the telonucleolus against the side which touches the external 

 plasmosome. This is well shown in figures 4, 6, 7, and 9 of plate 2. 



I am inclined to believe that this telonucleolus plays some part in 

 the development of the plasmosome content of the nucleus along with 

 the multiple plasmosome found in the smaller torpedoes, but am not 

 prepared to say what part, until I have completed some histogenetic 

 work now partly done. The telonucleoli are not found in all of the 

 cells and are sometimes hard to find. 



Another content of the nucleus consists of a number of small spherical 

 bodies which, on account of their high refrangency, sharp spherical 

 outline, as well as their strong chemical affinity for basic dyes, I shall 



