The females of the Embiidæ are comparatively large, wingless and symmetrically formed, the males have the abdomen more or less distorted (except species 17, 18 and 22). The males of probably all the species are dimorphic, being wingless (not dealated) or winged. The wings arise from invaginations at a pre-nymphal instar. A nympha-stage with larva-like body is undergone. Venation varies with the species, and generally is-double, represented by true veins and pigment lines. The thickened veins of texana are few. Copulation occurs within the nests. The carriage of the male abdomen is attributable to its function. The facets of the Embiid eye are quite like those of a newly-hatched grasshopper. The entire family is tropicopolitan and prefers the humidity of the coast-region. Its extended island-distribution appears to be in part artificially effected. Brazil, the Mediterranean region and India seem to be the points of differentiation of the groups Olyntha, Embia and Oligotoma, respectively. The internal anatomy presents a generalized type. But little change is undergone during metamorphosis. The oviducts of an old female may be as large as the alimentary tract. The females have all available space occupied by the fat body and later by the developing eggs. The brain is much less developed than the ventral nerve chain. The visceral system comprises four prominent unpaired cephalic ganglia. Embryonic growth is completed in about a month. The eggs have a unique micropylar apparatus and are not oriented in the female in their definitive position. The history of the embryo conforms with the Orthoptera, of which group the family is considered as a conservative and ancient branch.