MINUTE ANATOMY OF THE HEART. 257 



enter into communication with ganglion cells. These, united 

 into groups, lie on the external surface of the fasciculi of fibres, 

 and sometimes form small detached ganglia, which are con- 

 nected with the nerve by a peduncle. Accumulations of cells 

 of materially larger size do not occur, whilst in particular the 

 enlargements of the nerves perceptible to the eye are occasioned 

 simply by the penetration into their substance of connective 

 tissue, accompanied by large vessels. 



The relation of the fibres to the ganglion cells can be better 

 studied in the cardiac nerves of the frog than in the sub-peri- 

 cardial nerves of mammals, as the former spread out in the thin 

 interauricular septum, and are very well known in regard to 

 their course of distribution, in consequence of several special 

 works having been devoted to them (C. Ludwig, Bidder). The 

 greater number of ganglion cells exhibit the structure peculiar 

 to the cells of the sympathetic, in which from one and the same 

 pole, besides the so-called straight fibre, there originates also 

 the spiral fibre of Arnold and Beale, which has elsewhere been 

 fully described. Besides these, however, as has been shown 

 by various observers, true bipolar cells are present, and, lastly, 

 also ganglion cells, characterised by the peculiar mode of their 

 arrangement, which, if we accept the view of Auerbach,* are 

 found " in opposition," that is to say, two pear-shaped cells 

 lie in a common sheath with their flat sides applied to one 

 another, whilst the nerve fibres issuing from their pointed ex- 

 tremities course in opposite directions. The approximation of 

 such binary cells being very close, especially when they are exa- 

 mined in the fresh condition, they may easily be mistaken for 

 simple bipolar cells. No spiral fibre is here present. 



Auerbach found this form of ganglion cell in the plexus myenteri- 

 cus, Bidder in the auricular septum, and I myself in other sympathetic 

 ganglia. According to my views, those cells from which two straight 

 fibres can be seen to issue, belong to the same category, since as 

 many even as three small ganglion bodies may be found invested by a 

 common capsule. 



Since the influence of the nerves on the activity of the heart has 

 been more accurately investigated, the view has generally been ad- 



* Virchow's Archiv, Band xxx., p. 458. 



