MIXUTE ANATOMY OF THE HEART. 



261 



the individual bundles are composed of closely compressed 

 fusiform cells. In fig. 43, two trabeculse are exhibited from 

 the auricle, partially detached from each other. Fine nerve 

 fibres, with the ordinary nuclei, intervene between them, and, 

 after frequently undergoing subdivision, become closely applied 

 to the muscular fasciculi. (The branch a runs beneath the 



Fier. 43. 



Fig. 43. Trabeculso of muscle from the auricle of the Frog, with 

 the nerves. 



fasciculus.) Fine fibres are, as usual, given off from the cha- 

 racteristic triangular nuclei, which penetrate into the interior 

 of the fasciculus, and it may then easily be seen that the 

 nucleated fibre c lies in a space between the muscle cells. By 

 carefully isolating the tissues, very fine branched fibrils may 



