Fig. 7.

The cell masses in the pallium of actinopterygian fishes. Transverse sections through the telencephalon of the urodele amphibian Ambystoma tigrinum (a), and the cladistian Polypterus ornatipinnis (b), and through the rostral (c, e) and caudal parts (d, f) of the telencephalon of the teleosts Gasterosteus aculeatus (c, d) and Danio rerio (e, f). In a–f, the course of radial vectors and the boundaries of the principal cell masses are shown to the left; the cytoarchitectonic organization and the course of the olfactory tracts passing to the pallium are shown to the right. The open arrows in a and e indicate streams of cells, which migrate tangentially from the subpallium to the pallium. g–k Summary diagrams showing hypothetical shifts of cell masses in the pallium of actinopterygian fishes, according to Sheldon (1912) (g), Northcutt and Braford (1980) (h), and Yamamoto et al. (2007) (j, k). For explanation, see text