3 GO BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 



has found what he calls " Kornchenkngelu." Judging from his figures 

 of them, they do not look much like the " Kornchenkugelu " of the 

 Muscidae, nor does their migration into the lumen of the intestine agree 

 with what has been found in Diptera. Moreover, he states that these 

 phagocytes are not numerous enough in the region of the midintestine 

 to account for the degeneration of the muscles of this region, and conse- 

 quently infers that there is chemical degenex'ation as well as phagocyto- 

 sis. Such different methods of degeneration in similar muscles of the 

 same animal is improbable. But the principal reason for believing that 

 there is no phagocytosis of these muscles in Thymalus and other Cole- 

 optera lies in the exact similarity of all their changes to those occurring 

 in the muscles of the leg type. In these muscles it can be stated Avith 

 certainty, not only that there is no phagocytosis, but also that the 

 larval muscles metamorphose into the imaginal muscles instead of 

 degenerating. 



The typical " Kornchenkugeln " which Deegener finds, but which 

 Rengel could not find, are met with in Thymalus. That is to say, there 

 are to be found leucocytes containing bodies many of which would 

 answer the description given by Deegener, but these leucocytes are not 

 such " Kornchenkugeln " as Weismann found. This is evident from 

 some of the appearances reproduced in Figures 40-48 (Plate 7). 

 These all represent leucocytes found in old pupae magnified 1600 

 diameters. Figures 43 and 46 look like leucocytes containing de- 

 generating nuclei, and there is a possibility that such may be the true 

 explanation of some of them ; none of them, however, are nuclei from 

 the intestinal muscles. Figures 40, 42, and 47 show inclusions which 

 certainly are not degenerating nuclei, and since there are found transi- 

 tional stages (Figure 48) to the first mentioned conditions, it is probable 

 that all of the inclusions are of the same kind. The most probable 

 interpretation of them is that they are intracellular parasites. This 

 view is strengthened by the presence of apparently similar bodies in 

 the intestinal epithelium of resting larvae. Also, bodies similar to the 

 deeply stained portions of Figure 40 aro found very numerously in the 

 body cavity and lumen of the intestine of old pupae and young imagines. 

 The true nature and relationship of these bodies cannot be stated with 

 certainty as yet, but whatever they may be, very few, if any of them, 

 can be called " Kornchenkugeln." 



Concerning the formation of the intestinal muscles of the imago, my 

 observations, again, are in harmony with those of Reugel, and disagree 

 with those of Deegener. The reconstruction of the intestinal muscles 



