HuBER, Sympatlietic Ncn'otis S)'stem. 87 



granules an almost colorless and apparently structureless ground 

 substance may be seen. These observations confirm very 

 closely results obtained by Dogiel (25) with thiis method. 



Dehler (26) has described a centrosome in the sympathetic 

 ganglion cells of the frog. This is, as far as I am aware, the 

 only observation of this structure in sympathetic nerve cells, 

 although Lenhossek (27) had previously drawn attention to its 

 existence in the spinal ganglia of the frog, and Miss Margaret 

 Lewis (28) has quite recently found it in some large nerve cells, 

 which she describes as giant cells, in an annelid belonging to 

 the Maldaniae family ; and Schaffer (29) in the head-ganglia of 

 Petromyzon. 



The nuclei of sympathetic neurons are as a rule only 

 imperfectly stained in methylen-bluf.-. They are relatively 

 large and often have an eccentric position, nearer the pole, op- 

 posite the one from which the neuraxis arises. Nucleoli may or 

 may not be observed. 



I wish here briefly to refer to the curious fact that in 

 some of the rodents — rabbit, hare ;and Guinea pig — a large 

 number of the sympathetic neurons possess two or even three 

 nuclei. Attention was drawn to thif; fact, many years ago, by 

 Schwalbe (30), and .has quite recently been the subject of a 

 special communication by Apolant (31). Schwalbe showed that 

 in the ganglia of the sympathetic chain of young rabbits, mono- 

 nuclear ganglion cells and ganglion cells with two nuclei were 

 to be found ; and that the number of the mono-nuclear cells de- 

 creased with the age of the animal. He states that in old ani- 

 mals the mono-nuclear ganglion cells of the sympathetic are bi- 

 polar, while those with two nuclei are multipolar. 



That these are not simply degenerated cells, Apolant (31) 

 argues may be shown by the fact the multinuclear sympathetic 

 nerve cells are to be found in embryo rabbits of the third week. 

 They develop, he states, by an amitotic division'of the nuclei 

 of the mono-nuclear cells. Apolant discusses^ the question, 

 whether the cells with two nuclei might have two neuraxes, as 

 suggested by Guys. His results with the methylen-blue 

 method seem to have been unsatisfactory, and as this question 



