190 



XEEDHAM. 



[VOL. I. 



themselves becoming the nuclei of new muscle fibers. The 

 single fat globules which they often carry with them and 

 sometimes retain, even after they have become associated with 

 the muscle rudiments, enable one to follow them easily from their 

 former situation into this new one. 



There is no destruction of any larval tissue by phagocytes 

 during metamorphosis, but after the imago stage has been entered 

 upon, large numbers of phagocytes appear in the midst of the 



fat along the sides 

 of the abdomen. 

 There are numer- 

 ous embryonic or 

 undifferentiated 

 cells lying along 

 the sides of the 

 body in the lar- 

 vae ; and these, I 

 believe, begin to 

 penetrate the fat 

 masses toward the 



61101 OI trie pll- 



r-jql ct-acrp "Pi " TO 

 & CV 



shows the appear- 

 ance they present in a recently transformed weevil. Up to 

 this time the fat filling the abdomen has not been greatly 

 reduced, except in the anterior end ; the change of form in the 

 abdomen in passing from larva to imago is slight as compared 

 with that of other parts. But it is clear that the internal meta- 

 morphosis is only well under way when the external is com- 

 pleted. This reserve store of fat is for the completion of the 

 still weak organs of the imago, and for nutrition during the ten 

 long months of inactivity remaining before the flags bloom and 

 feeding begins again. 



After calling attention to some of the interesting features of 

 post-embryonic development, I would not close this little paper 

 without mentioning the exceptional availability of this species 

 for laboratory study. On a single trip to a favorable flag clump 

 during the latter part of July in this latitude, one may gather in 



FIG. 10. Phagocytes attacking the fat ; the section is through the abdo- 

 men of a recently transformed imago. /, phagocytes ;_/", fat. (From 

 a preparation made in my laboratory by Miss Elizabeth Andrews.) 



