Fig. 5.

Three-dimensional reconstructions and ultrastructure of matrix cords in developing stroma of embryonic chick cornea. At late E5 (+22 h) cords (arrows) extend from epithelium (e) into vicinity of migrating neural crest cells (nc) (A, B). Globular matrix beads (arrows, C) appear attached to cords. Matrix cords are in contact with migrating cells (arrow, D), in this case a prospective keratocyte, and are continuous with epithelial basal lamina (arrow, E), which frequently exhibits conical protrusion into subjacent stroma (arrow, F). Transmission electron microscopy shows microfibrillar substructure of matrix cord (G). Bar, 10 μm: A, C; 5 μm, B; 2 μm: D - F; 250 nm, G.