Fig. 9. Modes of veil dynamics in the neuronal growth cone. (1) Veil protrusion associated with filopodia at the front and rear of the growth cone. Branched filaments can arise from the veil network and merge into the filopodia or can occur off existing filaments in the filopodia. (2) Veil protrusion along a single filopodium, either crawling along the side of the filopodium (2a) or arising de novo off the shaft of the filopodium (2b). (3) Veil protrusion independent of filopodia. The veil network appears to be similar to lamellipodial network seen in nonneuronal cells. (4) Retraction at the front and rear of the growth cone. The veil network becomes very sparse and some filaments are seen aligned and bundled, parallel to the membrane.