Painted anatomical domains. Fourteen regions of the central nervous system in the CS17 specimen have been defined and painted. Forebrain, red (secondary prosencephalon), dark orange (prosomere 3 including ventral thalamus), light orange (prosomere 2 including dorsal thalamus) and yellow (prosomere 1 including pretectum); midbrain, light green; hindbrain; isthmus, dark green; various shades of blue and purple indicate rhombomeres 1–6 and the caudal medulla oblongata; spinal cord, dark red. (a; Additional file 2) In the Mpeg movie sagittal and transverse views of the painted model are shown, together with a representation of the 3D domains. The model is first sectioned in the transverse plane. This section plane has been matched to that of the histology sections shown in fig 2. As the section is moved through the model the corresponding position is displayed in the 3D box, and by a line on the sagittal section. The model is then moved through the sagittal plane, and the position shown by a line on the transverse section. A snapshot of the fourteen 3D anatomical domains (b), and two examples of painted sections that intersect several anatomic domains (i.e., are topologically nearly horizontal to the reconstructed transverse boundaries) (c). The position of the two digital transverse sections is indicated by white lines on the 3D view.