. A contribution to insect embryology. Insects. 56 WHEELER. [Vol. VIII. surface. The resemblance of the " micropyle " to the indusium is apparent at a glance {cf. Fig. 2, PI. I). I have followed the organ in Amirida through the later stages by means of sections and find that it persists for some time as a simple thickening of the blastoderm, still connected with the peculiar striated membrane which stands away from the surface of the blasto- derm at all other points. Finally, when the embryo has become flexed dorsoventrally and the body-walls are closed, it sinks into the yolk and is
. A contribution to insect embryology. Insects. 56 WHEELER. [Vol. VIII. surface. The resemblance of the " micropyle " to the indusium is apparent at a glance {cf. Fig. 2, PI. I). I have followed the organ in Amirida through the later stages by means of sections and find that it persists for some time as a simple thickening of the blastoderm, still connected with the peculiar striated membrane which stands away from the surface of the blasto- derm at all other points. Finally, when the embryo has become flexed dorsoventrally and the body-walls are closed, it sinks into the yolk and is absorbed. , Fig. V. Median section of the egg of Aniirida maritima. blastoderm. , "micropyle"; Although much simpler in its structure, I do not hesitate to homologize this " micropylar" organ in Amirida and the Poduridae in general with the indusium of XipJiidmm. A pos- sible objection to this homology, on the ground that the indu- sium arises on the ventral face of the &^g, while the Podurid "micropyle" is dorsal, has little weight, since the organ bears in either case the same relation to the head of the embryo. Provided, therefore, the egg of Amirida were to acquire yolk. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Wheeler, William Morton, 1865-1937. Boston : Ginn & Company
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