Double in situ hybridization of VGAT and VGLUT.Whole mounts with anterior to the left. Whole mount scale bars are 50 μm. In A , C and F the dark purple staining shows VGLUT expression, while the red staining shows VGAT expression. B, D, E and G show a superimposition of brightfield and epifluorescence with VGLUT- and VGAT-positive neurons. A,B: Side view of a 18-hr neurula. C: Side view of a 24-hr larva. D: Magnified dorsal view of the larva shown in C. E: Magnified anterior part of the larva in C. F,G: Side view of the anterior third of a 30-hr larva.