THE SMALLER WATER STRIDERS. 987 



times vaguely yellowish; tarsi dark brown. Basal joint of antennas near- 

 ly as long as the others united, 3 shortest, 4 twice the length of 3. Length, 

 4 — 4.5 mm. 



Ocean Beach, Miami, Fla., Sept. 23 (Davis). Recorded also 

 from Lake Worth, Fla. Occurs occasionally along the Atlantic 

 coast as far north as North Carolina. 



Family XXXII. VELIIM] Amyot & Serville, 1843, 418. 



The Smaller Water Striders. 



Semi-aquatic Heteroptera of small or medium size, having 

 the body short, oblong or oval ; head as wide across eyes as 

 pronotum, declivent in front ; beak 4-jointed, reaching behind 

 front coxse, joint 3 longer than the others united ; ocelli ab- 

 sent; eyes small, coarsely granulated; antennae 4-jointed; pro- 

 notum fused with the mesonotum ; elytra usually wanting, 

 when present reaching tip of abdomen with connexivum 

 usually rather widely exposed ; legs relatively short, the hind 

 femora not or but slightly surpassing abdomen ; middle legs, 

 except in Rhagovelia, equidistant from front and hind ones ; 

 tarsi variable as to genus. 



The family is a small one, only about 25 species occurring in 

 North America. Its members have the legs fitted for walking 

 rather than rowing over the water film and, says Bueno (1916a, 

 53) : 



"They dwell, as do their larger cousins, the Gerrida?, wherever there 

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

 er, 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 surface; 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, are 

 such daring navigators as are the larger Gerrida?, but pass most of their 

 time near the banks, often making short journeys out over the land 

 where they move about with ease." 



The principal literature treating of our eastern species is by 

 Uhler, 1884, 1894a; Champion, 1898; Bueno, 1907a, 1916a, 

 1923, 1924, 1924a; Parshley, 1921a; Drake, 1919b and 1920. 

 Our eastern species are distributed among three genera. 



KEY TO EASTERN GENERA OF VELIID.E. 



a. Front tarsi 2-jointed; fourth antennal (in our species) longest. 



I. Microvelia, p. 988. 



