88 Bulletin of the Brooklyn Entomological Society Vol. XVI 



the pronotum. In his paper on the European species of Micro- 

 velia (Note sur les deux Microvelia d'Europe. Ann. Mus. Nat. 

 Hungarici, XIV: 68-71, 1916, 2 figs.) Horvath makes use of 

 these modifications in the mesonotal structure to distinguish the 

 two species, and both conditions are illustrated by American 

 forms, for in fontinalis (fig. 3) the mesonotum is concealed as in 

 pygmaea (Dufour) Horv., while the rest of the species noticed 

 below, with one exception, have the other type of structure, like 



Fig. I. Microvelia hinei Drake. — a, male; b, female; c, nymph, 

 (x 40.) Fig. 2. M. borealis — a, male; b, female, (x 20.) Fig. 

 3. M. fontinalis — male, (x 17.) I-VII, dorsal abdominal seg- 

 ments ; pr, pronotum ; ms, mesonotum ; mt, metanotum, metanotal 

 triangles; g, genital segment. 



