FORE-GUT OF CORYDALIS CORNUTUS L. 607 



obscuration of the finer discs, Krause's membrane and Hensen's 

 disc. The nuclei are more chromatic, large and more prominent. 

 This strikes one forcibly when comparing sections of the muscles 

 of the larva and the prepupa (figs. 17 and 19). The sarcoplasm is 

 also more prominent, though undoubtedly this is due to the great 

 contractions of the fibers. I do not find any marked differences in 

 the staining reactions of the fibers. Scattered among the muscles 

 are found a considerable number of leucocytes, which, however, 

 show no signs of special activity. They are more numerous in the 

 posterior region, particularly near the oesophageal valve. During 

 the larval life it is rare to find any leucolytes in the neighborhood 

 of the fore-gut. 



At the time of pupation the changes above outlined become more 

 marked. The cross striations are beginning to disappear, while 

 the outer portions of the circular muscles show in many places a 

 granulose structure. The cross striations are affected earliest 

 in the neighborhood of the nuclei and show first near the anterior 

 end of the oesophagus. As to why this degeneration should first 

 appear around the nuclei seems difficult to explain except on the 

 basis of the location of the greatest cytoplasmic activity near the 

 nuclei. This does not indicate auto-phagocytosis in any sense 

 of that word. It simply indicates that the chemical activity is 

 greatest where the cytoplasm is greatest and the liquefying 

 process proceeds outward from the nuclei as centers. This, I 

 think, is borne out by the facts shown in the degeneration in 

 the muscles of Corydalis. 



The sarcoplasm is constantly increasing in amount while the 

 nuclei are large and prominent (fig. 20). In cross-sections the 

 areas of Cohnheim do not stand out so sharply. As yet there is 

 no noticeable change in the fibrillar structure except near the 

 nuclei. Leucocytes are distributed somewhat sparingly around 

 and among the muscles, but they do not show any activity in the 

 destruction of them. 



At a slightly later period the cross striations have almost 

 completely disappeared except near the posterior end of the fore- 

 gut, while here and there scattered strands show a faint cross 

 striate condition. The greater part of the circular muscles have 



