MINUTE ANATOMY OF THE HEART. 



245 



striated, sometimes contains fat drops even when apparently 

 healthy, and presents nuclei that are arranged at tolerably 

 regular distances from one another. In the several round or 

 oval disks which are found in sections perpendicular to the 

 direction of the fibres, the nucleus is always in the centre,* 

 excepting in those cases where, on account of the thinness of 

 the section, disks without nuclei happen to be exhibited (fig. 

 39). The more or less wide fusiform spaces of the contractile 

 substance in which the nuclei lie are filled in the larger speci- 

 mens with a granular mass, which sometimes (in man) is of a 

 yellow colour (fig. 40, A). 



Fig. 40. 



Fig. 40, A. Muscular fibres from the heart of Man, divided by trans- 

 verse septa into separate nuc'eated portions. From a preparation pre- 

 served in alcohol after having been macerated in a 1 per cent, solution 

 of potash, and in glycerine. 



B. Two laterally adherent muscle cells from the Guinea-pig. From 

 a specimen that had been treated with acetic acid and solution of 

 common salt. 



The interpretation of the nature of the so-called muscular fibres 

 of the heart is different from that applicable to those of the vo- 



* Bonder's Physiologic des Menschen, 1859, p. 23. 



