230 WILSON P. GEE. 



vacuoles are to be noted in the cytoplasm. The chromatin has 

 gathered into irregular masses along the sides of the adjacent 

 cytoplasm (position of former nuclear membrane) and the linin 

 appears in masses which have separated from the chromatin 

 material. In an imago two or three days after emergence, but 

 which had been kept enclosed in a small dish, the degeneration 

 of the nucleus is seen to have proceeded further. The cell does 

 not, however, present an essentially different appearance to that 

 shown in the imago two or three hours after emergence. This 

 third-day imago was the latest stage of which material \\ as ax-ail- 

 able. It would be interesting to determine from older imagoes 

 whether the oenocytes entirely degenerate and are taken up for 

 the purpose of general nutrition of the tissues, thus affording a 

 reserve food supply in addition to their secretory function. This 

 latter view would, however, be hard to understand considering 

 the short life of these insects, and also the fact that egg-laying 

 goes on shortly after emergence from the pupal case. 



Various functions have been attributed to the cenocytes. 

 Landois (1865) gave to them the name "Respirationszellen" and 

 assigned to them a place in the respiratory system. Graber 

 (1873), in his early work, speaks of them as unicellular glands, the 

 secretion of which was of unknown function; later, howi-vrr, he 

 holds that they are metamorphosed into the fat-body, and give 

 rise to blood corpuscles. Berlese (1899) considers the cenocytes 

 as excretory in function, as does also Koschevnikov (1900). 



Anglas (1900) says: "Ce fait permet d'affirmer qu'ils s6cretent 

 autour d'eux des ferments. Aussi les considerons-nous cominc 

 des cellules glandularies (nees de l'hypoderme) et jouant le role 

 de glandes a secretion interne, mais de glandes dissocies." Ver- 

 so n (1891-2) considers them as secretory in nature as do also 

 Rossig (1904) and Weissenberg (1907). 



Holmgren (1900) in Apion flavipes, experimenting by injecting 

 small quantities of powdered methylene blue and alizarin-cyanin 

 into the body cavity, came to the conclusion that they were 

 excretory in function. He found that the cenocytes took up the 

 color in much the same manner as the Malpi.uhian tulirs, tin- 

 nucleus of the cenocyte showing signs of staining somewhat rarlirr 

 than the nuclei of the latter organs. Three hours after injection, 



