MUSCLE DEGENERATION IN AMPHIBIA 79 



represent the chemical nature of the granules as well as 'hemo- 

 globin-nature,' for both muscle tissue and erythocytes contain 

 phosphorous-containing compounds. The term 'hemoglobin- 

 nature' does not seem to be comprehensive enought to express their 

 chemical nature. The simple phrase " Zerfallsprodukte der 

 Erythrocyte!!" to which I add 'products of degenerating muscle 

 tissue,' would express a greater probability of the granules con- 

 taining other elements beside hemoglobin, than does the term 

 ' Hiimoglobinnatur . ' 



To give a detailed account of the different theories relative to 

 the degeneration of muscle tissue in different classes of animals is 

 beyond the scope of this paper. Observations by different inves- 

 tigators of various animal groups indicate that the processes 

 involved in the degeneration of muscle tissue vary considerably. 

 Briefly stated, the interpretations of different workers of the man- 

 ner by which a muscle degenerates and the part played by the leu- 

 cocytes in this phenomenon has resulted in the establishment of 

 three general views: (1) a purely aphagocytic process by which 

 the muscle fibers undergo liquefaction, either through the activity 

 of internal conditions of the fiber or through the action of the 

 fluids surrounding them; (2) a purely phagocytic process by which 

 the phagocytes break up the muscle fibers into fragments which 

 are taken up and removed by them ; (3) by a combination of the 

 aphagocytic and phagocytic processes. The views enumerated 

 above are stated only in a general way and the theories as worked 

 out by different investigators have detailed modifications. 



Barfurth ('87), in his work on the frog larvae, came to the con- 

 clusion that a muscle degenerates independently of the action of 

 phagocytes. The myofibrillae break up into comparatively long 

 fragments, bundles of which make up the sarcolytes. The cross- 

 striations are present in the sarcolytes when they are first formed 

 but gradually disappear as the muscle fragments undergo disso- 

 lution. The liquefaction of the fragments takes place within 

 the sarcolemma, which is comparatively resistent to the action of 

 the liquefacient, and disappears only after the sarcoh^tes have 

 been reduced to granules — the debris of degeneration. The ini- 

 tiatory causes of degeneration are unknown to him but he thinks 



