Fig. 4. Light micrograph showing transverse sections through the ventral anterio-median retina of a lycosid wolf spider (species A). (A) Low-power view, showing type 1 receptors (1) and both distal (2d) and proximal (2p) type 2 receptors from the tiered region. The blind strip (bl) between these layers in clearly visible in this section. Scale bar, 55µm. D, dorsal; L, lateral. (B) A higher power view of the tiered region, showing orthogonal type 2 receptors in the distal (d) and proximal (p) layers and longitudinal, vertically extended intermediate segments of the distal receptors (arrowheads). Scale bar, 25µm.