THE EMBRYOLOGY OF THE HONEY BEE 91 



the formation of this body are usually larger and rounder than 

 those contained within the latter, moreover they are not present 

 in sufficient numbers in the immediate neighborhood of the ceph- 

 alo-dorsal body to make it seem probable that they contribute 

 largely to its formation or growth. It is also possible that the 

 number of nuclei may be increased by either direct division or 

 fragmentation of the nuclei originally present, but this could not 

 be demonstrated to be the case, although in many instances this 

 was suggested by the appearance of the nuclei. The latter are 

 so small and so frequently crowded closely together that it was 

 found impossible satisfactorily to decide this question. It is, 

 however, certain that the nuclei differ among themselves in size, 

 and that they are also very frequently lobed or constricted. 



Soon after reaching its maximum size the cephalo-dorsal body 

 during Stage VI breaks up into amoeboid cells or small syncitia 

 containing one to several nuclei. Some of these wander ventrad 

 towards the center of the egg (Fig. 30), but many remain near 

 the dorsal surface of the yolk. At Stage VII the remnants of thet 

 cephalo-dorsal body are still recognizable at the cephalic end of 

 the egg as irregular branching islands of rather pale granular 

 cytoplasm enclosing one or more small nuclei. The outlines of 

 the nuclei are always irregular and often faint, and when grouped 

 closely together as is frequently the case, many of the nuclei ap- 

 year to be in process of fusing with one another (Fig. 34C). At 

 Stage VIII the remains of the cephalo-dorsal body are evident, 

 lying close beneath the anterior mesenteron rudiment, near its 

 posterior end (Fig. 8yA,CB). From this point they travel to- 

 ward the caudal pole of the egg as if drawn by the rudiment until 

 they reach the point of junction of the anterior and posterior 

 mesenteron rudiments. During this period the vestiges of the 

 cephalo-dorsal body usually present the appearance of a thin layer 

 of slightly yellowish protoplasm, containing a few nuclei which 

 are situated near its inner surface, as shown in figure 87A, CB. 

 In some preparations, however, the cephalo-dorsal body seems to 

 have remained undiminished in size up to Stage VIII or IX. It 

 is then quite conspicuous and plainly evident even at a low mag- 

 nification. In these cases the appearance is almost precisely like 

 that figured by Petrunkewitsch (1902, Fig. 8) for the drone egg. 



