FORE-GUT OF CORYDALIS CORNUTUS L.' 605 



chemical and physical change in the muscle substance before leuco- 

 cytic intervention. The activity of the leucocytes may be great 

 (Mercier, Vaney, etc.) or very unimportant (Deegener, Karawaiew, 

 etc.). The preceding chemical changes may be .slight or very 

 marked. 



3. The lyocytic hypothesis of Anglas . ('00). According to 

 this view there is no engulfing of sarcolytes but an extracellular 

 digestion by means of diastases excreted by the leucocytes. The 

 tissues thus dissolved are absorbed by the leucocytes. This 

 process Anglas designates 'lyocytosis.' 



4. The auto-phagocytic theory of Metschnikoff for Amphibia, 

 De Bruyne and Russ for insects. According to this theory some 

 of the muscle nuclei surround themselves by protoplasm and 

 constitute true phagocytes (sarcoclastes or myoclastes of De 

 Bruyne). De Bruyne found this condition of the degenerating 

 muscles of Musca vomitoria while Metschnikoff regards it as the 

 normal process in the absorption of the tail in Anura. Russ ('08) 

 adopts this interpretation for the degeneration of the muscles in 

 Anabolia laevis, one of the Trichoptera. 



5. The purely chemical and physical hypothesis of Korotneff. 

 In a Tineid larva he finds the muscles are entirely broken down by 

 a chemical liquefying process without any intervention of phago- 

 cytes. Karawaiew adopts this view for the ants (Lasius niger), 

 Terre ('99) for the bee and Deegener ('04) for Cybister. Korot- 

 neff admits a true phagocytic activity where the metamorphosis 

 is extremely rapid, as in so many Diptera. He advocates the 

 hypothesis that where metamorphosis continues for a consider- 

 able time there is no phagocytic intervention, but on the other 

 hand phagocytes play the all-important role where the changes are 

 rapid. 



6. The theory of Berlese. According to this worker the first 

 change to appear is the separation of the sarcolemma and the 

 nucleus from the fibrillar part. This he calls myolysis. The 

 fibers are chemically dissolved whereas the nucleus with its plasma 

 survives — it is the living part of the cell capable of regenerating 

 new contractile fibers. The dissolution of the fibers (fibriolysis) 

 is probably caused by the extravasation of the intestinal contents 



