Description of Holotype: Shell small, fragile, white, base ovate, height about ½ the length, apex posterior, directly above the posterior margin of the shell. Anterior slope convex, posterior slope flat sided below the apex. Nucleus minute, greatly overhung by the succeeding part of the shell. Sculpture consists of 20 primary cords diverging from the apex; secondary cords develop on the anterior and lateral faces but do not reach the strength of the primary cords at the margin; concentric sculpture consists of narrow raised ridges that do not cross the primary ribs. Margin crenulated by rib extensions. The slit is long and narrow, almost 1/3 the length of the anterior slope; the lamellae along the fasciole are thin, raised nearly to the margins of the fasciole. Interior glossy, thickened near the slit, anal fasciole marked by thickened callus. Length, 4.6 mm, width, 3.6 mm, height, 2.3 mm (holotype).

Emarginula dictya differs from the 3 other eastern Pacific species of Emarginula in having weak concentric ribbing and consequently lacking the beaded sculpture at intersections of the ribs. It resembles E. sicula GRAY, 1825, of the Western Atlantic and Mediterranean. Emarginula sicula, however, is larger, more elevated, and the apex is near the summit rather than below the mid-height position as in E. dictya.
The name is derived from the Greek noun, dictyon, net, with reference to the fine reticulate sculpture.

Type Locality: Off San Felix Island, Chile, 26°20/S, 80°02'W, 170- 160 meters (93-87 fathoms), Anton Bruun, Cruise 17 station 676B, Menzies trawl, 12 July, 1966, 2 dead and slightly broken specimens.