Fig. 1. Schematic drawing of the position (A,B) and structure (C) of the ventral photophores of the hatchetfish Argyropelecus hemigymnus. A common chamber for the photocytes (p) is surrounded by a reflector (r) (B,C). There are several exits for light from the photocyte chamber. The exits contain pigmented filter (f) cells and, more peripherally, unpigmented transparent tissue called the gelatinous body (gb; C) (Bassot, 1966; Denton et al., 1985). Arrows indicate the main entrance points for nerve fibres through the reflector to the photocyte chamber found in the present study (C).