THE EMBRYOLOGY OF THE HONEY BEE 183 



Hirschler (1909) finds that in Donacia the oenocytes arise in 

 two ways. A part of them arise by migration from restricted 

 areas of eight of the abdominal segments, immediately caudad 

 of the stigmata, thus forming metamerically arranged groups. 

 Another part is formed by a sort of diffuse or irregular immigra- 

 tion from various parts of the ectoderm, but particularly from 

 the vicinity of the pericardial septum and the proctodaeum. 



The oenocytes of the honey bee were first described by Wie- 

 lowiejsky (1886) and have been studied in detail by Koschev- 

 nikov 19 (1900, 1905), and — in connection with the metamorphosis 

 — by Anglas (1900). These investigators agree that in the larval 

 honey bee the oenocytes are represented by "certain cells which 

 are of great size, not vacuolated, their protoplasm staining strongly 

 with borax carmine, and having large regular oval nuclei. . . . 

 They are to be found in the depths of the body surrounded on all 

 sides by the fat body and sometimes packed close against the 

 walls of the Malpighian tubules. I never observed two nuclei in 

 any of these cells. During histolysis, they float free in the body 

 cavity. The largest of them are truly gigantic, measuring 176 

 micra with a nucleus 56 micra in diameter." 20 One of these cells, 

 together with the surrounding fat cells, in a larva four days old, 

 is illustrated in figure 70A. In younger and smaller larvae the 

 oenocytes are smaller, but their size, as compared with that of 

 the fat cells, remains about the same. An oenocyte surrounded 

 by three fat cells, from a recently hatched larva, is represented in 

 figure 70B. It will be noted that in this case the magnification 

 is 1 107 diameters, while in that of the older larva (Fig. 70A ) the 

 magnification is only 580 diameters. A fair conception of the 



19 Glaser (1912) has expressed doubt in regard to identity of the cells 

 described by Koschevnikov with the oenocytes of other insects on the 

 ground of Koschevnikov's statement that he has observed the oenocytes 

 in the act of engulfing fat cells. Without attempting to weigh the merits 

 of this objection, it may be remarked that the oenocytes of Koschevnikov, 

 in the larval stages at least, correspond morphologically with the oenocytes 

 of other insects more closely than any other cells within the body cavity, 

 and, if these are not truly oenocytes, it would be necessary to assume that 

 such cells are either non-existant in the bee, or else that they are morpho- 

 logically different from those of other insects. It is of interest to note in 

 this connection that Anglas (1900) states that he has never seen them act 

 as phagocytes. 



20 Koschevinkov (1909). 



