Journal of morphology . nt decrease in the space between the body walls andthe chorion. The columella and the remains of the inner indu-sium are held together and thus temporarily prevented fromcomplete disintegration by the thick cuticle of the cuticle still envelops the embryo and extends forward tothe anterior pole where it seems to be attached to the inner faceof the outer indusium. Passing further inward we nextmeet with the first larval cuticle (Iv. c^), which has been shed,and the second larval cuticle {Iv. c~), which is still in organic No. I.] CONTRIBUTION TO INSECT EMBRYO
Journal of morphology . nt decrease in the space between the body walls andthe chorion. The columella and the remains of the inner indu-sium are held together and thus temporarily prevented fromcomplete disintegration by the thick cuticle of the cuticle still envelops the embryo and extends forward tothe anterior pole where it seems to be attached to the inner faceof the outer indusium. Passing further inward we nextmeet with the first larval cuticle (Iv. c^), which has been shed,and the second larval cuticle {Iv. c~), which is still in organic No. I.] CONTRIBUTION TO INSECT EMBRYOLOGY. 33 connection with the hypodermis. In a little later stage thanthe one here described the columella and the conical lump ofinner indusial elements have disintegrated, and can no longerbe distinguished from the granular amniotic serum. The changes in the configuration of the embryo since itsarrival on the ventral yolk, relate mostly to the first the antennae are of about the same thickness as the -5XC. Fig. IV. Sagittal section through the anterior pole of a Xiphidiu7n embryo, with pig-mented eyes, ch., chorion ; cL, columella ; s}-. c, Blastodermhaut; sr., serosa ;uid^ + a7n., remains of the inner indusium and amnion ; ind^, outer indusium ;ind^ s., secretion of the inner indusium; am. s., amniotic secretion; /v. c^, firstlarval cuticle ; h. c~, second larval cuticle ; dr., brain ; e., eye. legs. The dark line running parallel with their inner edges,and distinctly marked in Fig. 9, is in section seen to be a meso-dermal partition dividing the cavity of the appendage into twotubular sinuses. The antennas grow directly tailward till theirtips reach the femorotibial joint of the hind legs, when they di-verge laterally, describe an arc, and then grow forward. Whenthe tips have reached the head further progress is arrested 34 WHEELER. [Vol. VIII. by the envelopes, but as the growth of the appendages doesnot cease, the arcs surrounding the hind legs gradually move
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