XXXIII, XXXIV. Families MICROPEZID^, 

 TANYPEZIDJ3. 



Fig. 102. Caiobaia univittata, enlarged. After Washburn. 



These two groups, often associated together, present 

 such important structural differences, and the resem- 

 blance of the insects composing them is so slight, that 

 their separation seems entirely proper. 



Tanypezidce. Head broad, subhemispherical, the occi- 

 put concave, the eyes very large, the posterior orbits very 

 narrow, the cheeks also narrow; front rather narrow, 

 with bristles on upper half only. No vibrissal bristle. 

 Antennae more or less elongated, decumbent. Venation 

 complete; posterior basal cells small; first posterior cell 

 narrowed in the margin. Legs long; tarsi longer than 

 the tibiae; tibiae without preapical bristle. 



A single genus Tanypeza, with a half dozen species 

 perhaps, is all that can be definitely referred to this 

 group. It will be readily recognized from the accompa- 



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