246 BUMPUS. [Vol. V 



assign to the outer area the peripheral portion of the compound 

 eye, to the converging ridges the primitive nervous tract or 

 optic lobes, while the median swellings will probably turn out 

 to be the cerebral lobes, though I have as yet been unable to 

 trace the structures actually into the stages which are so ably 

 worked out by Parker ('90). 



It will be observed that the striking triangular masses of 

 nuclei, heretofore called the procephalic lobes, have quite dis- 

 appeared, the nuclei in their former site now being no more 

 closely arranged than they are on other portions of the surface 

 of the egg equally distant from the embryo. An examination 

 shows that their earlier arrangement has been given up. They 

 may have disappeared completely. There has also been a 

 local ecdysis. A heart-shaped piece of cuticle elevates itself 

 from this portion of the egg, and splits away anteriorly and 

 laterally, following the outline shown in Plate XIV, Fig. M. 

 Posteriorly, the flap is connected with the first antennas, and so 

 closely that it is with considerable difficulty that the piece can 

 be removed, without at the same time removing the antennae. 

 The anterior point of the flap is, moreover, in every case con- 

 nected with the investing " Blastodermhaut." On removing the 

 heart-shaped flap of cuticle, two large bowl-shaped depressions 

 (PI. XIX, Fig. 1, B.D) are revealed. These are, in favorable 

 specimens, quite as deep as they are wide, and are symmetri- 

 cally placed. Their signification I am at a loss to surmise, 

 though I have been at times inclined to think that they may 

 arise from the action of reagents upon the underlying "serum." 

 It is possible that they may represent a "dorsal organ." 



A median line of approximated nuclei now extends from the 

 anterior and posterior portions of the embryo nearly around the 

 egg, in nitric acid preparations appearing as an encircling white 

 band. 



The sections of this egg are specially instructive. Fig. 13 

 shows that the stomodaeum (St.) is no longer a depression, but 

 has become a tube, and, bending anteriorly, reaches well into 

 the yolk. The upper lip has become thickened, and has closed 

 down over the primitive mouth. In the neighborhood are many 

 mesodermal cells and chromatin grains. The hind-gut is clearly 

 seen at Hd., though there is no lumen, this portion of the primi- 

 tive alimentary tract being only marked out by the parallel rows 



