88 Journal of Comparative Neurology. 



could alone be approached by a study of preparations obtained 

 with this method, be leaves the question unanswered. 



In methylen-blue preparations of sympathetic ganglia of 

 half grown rabbits and of full grown Guinea pigs, fixed in am- 

 monia molybdate and sectioned, I find that, in the semilunar 

 ganglion, sympathetic cells with two nuclei are numerous, al- 

 though mono-nuclear cells may easily be found. I find no fixed 

 relation between the number of nuclei in a given cell and its 

 shape, as has been stated by Schwalbe, i. e. , bipolar cells be- 

 ing mono-nuclear and multi-polar cells being multi-nuclear. 

 Multi-polar cells with one nucleus were found, as well as bi- 

 polar cells with two nuclei. In such multi-nucleated neurons in 

 which it was possible to designate the neuraxis, only one was 

 found. The sympathetic ^ganglia of rabbits and Guinea pigs, in 

 which neurons with two nuclei were observed, are in all other 

 respects similar in structure to the sympathetic ganglia of verte- 

 brates having only mononuclear neurons, as will be shown later. 



Apolant (3 i) suggests that ' 'The development of two nuclei, 

 in the cells in question, is in close inter-relation with the growth 

 of the cells, and in this way — the nucleus of a mono-nuclear 

 cell attains a relatively large size (as he has shown by measure- 

 ment), it then divides amitolically, this reacts on the cell body 

 and causes it to grow proportionately. The process is therefore 

 not a functional one, but a biological one." Apolant does how- 

 ever not explain why this should take place only in certain gan- 

 glia of the rabbit and not in others ; in the ciliary ganglion, for 

 instance, only mono-nuclear cells are found ; and why in certain 

 rodents and not in others, he himself having shown that in the 

 sympathetic system of the rat, mouse and squirrel only mono- 

 nuclear cells are to be found, -^^his curious fact, it seems to me, 

 still awaits explanation. 



Capsule. — The cell body of a sympathetic neuron is sur- 

 rounded by a nucleated c?ipsule, which consists of cells resem- 

 bling endothelial cells. In multi-polar cells, the* dendrites pierce 

 this capsule. Whether the capsule extends out on to the den- 

 drites for any distance, I am unable to .say positively, although 

 the evidence points against such a view. It is generally stated 



