IX. Family SIMULIIDjE. 



Fig. 43. Simulium venustum; enlarged. After Washburn. 



Small flies, from one to six millimeters in length, with 

 thick, short legs. Head hemispherical; face short; 

 eyes round or reniform, holoptic in the male; no ocelli. 

 Antennae scarcely longer than the head, flattened or cyl- 

 indrical, ten-jointed; the two basal joints differentiated, 

 the others closely united. Proboscis not elongated, with 

 small, horny labella ; palpi incurvate, four-jointed; the 



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