278 REMAK, ON THE EMBRYOLOGICAL 



and their cell-nature ; but instead of stating what a muscle- 

 corpuscle is, or is said to be, how it originates, and how it 

 may be demonstrated, Schultze at once starts with the at- 

 tempt to trace the history of the development of the muscular 

 fibre, in order to make us understand the nature of the so- 

 termed muscle-corpuscles, from genetic considerations, and 

 afterwards to demonstrate their cell-nature. 



Although it is by no means my object or intention to sub- 

 vert the belief in the existence of special muscle-corpuscles, I 

 will nevertheless not leave the reader in doubt that, in my 

 opinion, the so-termed '' muscle-corpuscles" are the result of 

 various kinds of imperfect observations. In transverse sec- 

 tions of hardened muscular fibres, as, for instance, of the 

 frog, stellate anastomosing figures may occasionally be seen, 

 resembling the well-known connective tissue " corpuscles." 

 The appearance in question, however, has manifestly nothing 

 Avhatever to do with any cell or nuclear formation, but arises 

 simply from the circumstance that the contractile muscle- 

 cylinder breaks up into fibrils, around which, in consequence 

 of some kind of chemical or physical cadaveric differentiation, 

 portions of a substance possessing a different refractive power, 

 are deposited with a certain regularity, and thus constitute, 

 as it were, a system of connected septa or tunics around the 

 transparent fibrils. Again, I'ows of minute granules may 

 occasionally be seen proceeding from the extremities of the 

 well-known nuclei which lie between the sarcolemma and its 

 contents, and which thence assumes the aspect of a fusiform 

 cell. And, lastly, nuclei are said occasionally actually to 

 occur in the axis of the muscular cylinder, from which stellate 

 figures proceed. With respect to this, however, all I can 

 satisfy myself of is the fact, that in the Purkinjean muscular 

 fibres of the endocardium of the ventricles in the sheep and 

 goat, bodies are presented which should be referred to the 

 same category, and which have probably been the means of 

 adding to the confusion in which the subject is involved. 

 The Purkinjean fibres, like the rest of the muscular tissue of 

 the heart, are striated and anastomose with each other ; but 

 the nuclei lie, not between the sarcous cylinder and the sar- 

 colemma on the surface, but in the interior of gelatinous 

 globules of considerable size, by which the continuity of the 

 sarcous cylinder is interrupted from point to point, and which 

 are otherwise in contact or more intimately connected with 

 the sarcolemma. (This disposition is obviously intended to 

 interfere with the contraction of the muscular fibres, of the 

 very firm and elastic endocardium, so far as may be necessary 

 to prevent a complete emptying of the ventricles, which, at 



