The wasps belonging to this family, on account of the emarginate eyes in the females, and the abdomen being usually marked with yellow or white, closely resembles those in the families Myzinidæ and, scoliidæ, butmay be easily distinguished by the great difference in the legs, the middle coxæ being approximate, the outer face of the tibiæ being smooth,unarmed, without tubercles or spines, while the tarsi are without strong spines or bristles, and unfitted for digging.