A Detailed Organ Map of the Wing Disk of Calliphora Erythrocephala

Abstract

(1) Various fragments of the wing disk of the mature Calliphora erythrocephala larva were implanted into host larvae of the same age. Since mature imaginal disks exhibit a mosaic determination pattern, it is possible to correlate certain adult structures with particular disk fragments. (2) Primordia of morphologically distinguishable elements were presented in an organ map. The structures of the dorsal thorax, the dorsal part of the hinge, and the wing blade are mainly located in the disk proper. The ventral part of the hinge and the lateral thoracic structures turned out to be located in the peripodial membrane. (3) It is proposed to use new terms, inner layer and outer or peripodial layer, instead of the terms proper disk epithelium and peripodial membrane. (4) Several peculiarities found in the organ maps of the imaginal disks of Drosophila as published by other authors, strongly indicates that the peripodial layer comprises anlagen of adult structures in this animal also. Based on these indications, tentative organ maps of the peripodial layers of the different types of disks have been drawn. (5) Disk fragments containing the anlagen of either the ventral or dorsal wing surface, form both wing spread and veins, which indicates that the determination of the veins occurs on the two wing surfaces separately.