Some Observations on the Endocrine Centers in the Embryos of Anacridium Aegyptium, L. (Orthoptera- Acrididae) I- The Ventral Head Glands
1973
Küçükekşi, Süheyla
The ventral head glands of the embryos of Anacridium aegyptium L. were studied in subsequent stages histologically and beginning with the development of the glands, the morphological properties of the embryonic stages were considered. 1— These glands are a pair of structures and first appearing in embryos which have completed their rotation in the mycropilar end of the egg (at Katatrepsis). They are situated one on either side of the head and extend from a point on the epidermis just posterior to the dorsal primary head muscles to the suboesophageal ganglion and the adjacent epidermis.2- The glands are syncytial and have deeply staining nuclei of varying size and shape. At the active stage the nuclei increase in size and some become lobulated. Şome vacuoles appear in the cytoplasm which seems to form a network. 3- Throughout the embryonic stages one maximal period of activity appears. This coincides with the separation of the epidermis from the cuticle (embryonic moulting).Then the glands alşo seem to continue their function which is possibly connected with late embryonic developmental phenomena such as sclerotization and melanin deposition. 4- In the first hatchlings the glands are smaller in size.
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