Fig. 1. Drosophila embryonic brain anatomy. (A) DIC lateral view of an ES15 whole wild-type embryo stained with BP102, an antibody that recognizes CNS axons. The brain, which forms around the foregut, is outlined by the box. (B) Schematic representations of the brain and adjacent tissues at ES12 and late ES13. Mesoderm is in green, foregut ectoderm is in red, neuroblasts are in blue and neurons are in purple. (C) Dorsal view of the embryonic brain. b1 is the only segment visible in this view, and shows distinct separation into left and right hemispheres. (D) Lateral view of the embryonic brain, with b1-S3 visible. In this and the following figure panel, the outline of the foregut is shown by broken lines. Schemes represent a simplified arrangement of brain structures. CC, corpora cardiaca; CEC, circumesophageal connective; D/T, deutocerebral/tritocerebral neuron cluster; FC, frontal commissure; FG, frontal ganglion; PBC, preoral brain commissure; VNC, ventral nerve cord.