June, 1916 Bulletin of the Brooklyn Entomological Society 53 



lections. They dwell, as do their larger cousins, wherever there 

 is water to bear them on its elastic surface, except that, being far 

 smaller, they do not require such wide reaches for a contented 

 existence. Some may be found in the narrow confines of springs 

 and water-holes ; others in swift streams where the ripples braid 

 the waters; or again, in. salt coast estuaries; and finally, certain 

 ones seek the shelter of vegetation growing in slow-moving 

 streams, or on the edges of ponds. None, however,' counts among 

 its members such daring navigators as there are among the larger 

 Gerrinse. In the eastern United States, these small forms are ap- 

 parently as numerous in species as the larger; it is even possible 

 that there are more of the former, since the much more noticeable 

 Gerrids are far likelier to be collected than the inconspicuous 

 atoms here dealt with. The subfamily is divided into three gen- 

 era, which may be separated by the following key : 



1. Anterior tarsi 2-joInted; last antennal joint \ongtst. .Microvelia Westw. 



2. Anterior tarsi i- or 3-jointed; first antennal joint lorigest. 



3. Anterior tarsi i-jointed; intermediate tarsi longer than last, 3d- joint 



• split and with feathery hairs set in split. Rhagovelia Mayr 



4. Anterior tarsi 3-jointed; intermediate tarsi longer than last, but not 



split and. without feathery hairs Velia Latr. 



Velia Latreille, 1804, Gen. Crust. Ins., Ill: 133. — This genus 

 is represented in the Atlantic States by only two species, neither 

 of which is known as yet north of the vicinity of Washington, 

 D. C. Little seems to be known in regard to them. Miall limits 

 his remarks on the European V. currens to stating that it swims 

 under water more readily than Gerris and walks back-downward 

 on the surface film. The genus is dimorphic as to wings, which, 

 of course, makes certain structural changes in the thorax. Like 

 all their congeners, the species of the genus are predaceous. So 

 far as known, they are stream forms, as denoted by the names 

 of the two Europeans, currens and rivulorum. These congregate 

 in small schools, though our own have been taken only by ones 

 and twos. The European species overwinter as adults in moss 

 on stones. The eggs are deposited in spring on the vegetation 

 coming to the surface.* 



* C. Wesenberg-Lund, " Fortpflanzungsverhaltnisse : Paarung und Eia- 

 blage der Susswasserinsekten," Forts. Nat. Forsch., Halle, VII : 196. 



