424 ELMER L. SHAFFER. 



In studying the process of degeneration it is at once evident 

 that the mitochondria are concerned in the process. The first 

 noticeable change in the degenerating cells is that the mito- 

 chondria become larger and more deeply staining and the nucleus 

 often becomes polymorphic (Fig. 14). While the mitochondria 

 have increased in size, they have decreased in numbers and it 

 is quite evident that the large mitochondria have grown in size 

 by an agglutination of the smaller normal ones. I have de- 

 scribed a similar process in the degenerating spermatogonia of 

 Passalus (Shaffer, '17), but was unable to follow in detail the 

 succeeding stages of degeneration. In Cicada, the further pro- 

 cesses in the degeneration involve a continued agglutination or 

 coalescence of the mitochondria which results in the formation 

 of large bodies of globular form staining intensely (Fig. 15). 

 This process is continued (Fig. 16) until finally the degenerated 

 cell becomes a deeply staining mass with the nucleus barely vis- 

 ible. Often the large globules show vacuoles which I interpret 

 as being due to a partial dissolution of their substance by the 

 reagents used. 



Scott ('16) found that in experimental phosphorus poisoning 

 of white mice the mitochondria are the first elements of the 

 acinus cells of the pancreas to show any pathological changes. 

 They begin to loose their characteristic filamentous form and 

 finally agglutinate in large compact masses in the cell. "The 

 mitochondria in these agglutinated masses fuse to form droplets 

 possessing the characteristic properties of lipoids" (Scott, 'i 6, 

 p. 251), hence developing a fatty degeneration of the pancreas. 

 The significance of these observations of Scott is at once apparent 

 in connection with the degeneration of cells above described in 

 Cicada. The behavior of the mitochondria in the degenerating 

 spermatogonia of Cicada is essentially similar to their behavior 

 in the fatty degeneration of the pancreatic cells and I am conse- 

 quently of the opinion that the degeneration of the spermatogonia 

 is a fatty degeneration. 



Recently, Athias ('19) has studied the mitochondria in the 

 interstitial cells of the ovary of the bat, Vespertilion idee. The 

 mitochondria are present here in the form of granules and fila- 

 ments, which gradually become transformed into fat globules. 



