986 FAMILY XXXI. — GERRID^E. 



June — August (Barber). When taken in a water net it is a 

 very active leaper in its efforts to avoid capture, while the other 

 two species run rather slowly about on the bottom of the net. 

 Its known range extends from New England west to Michigan 

 and Illinois and southwest to Florida, Louisiana, Arizona and 

 Central America. The only Florida record to be found is that 

 of Uhler (1884, 270), viz.: "Massachusetts to Florida." Only a 

 few fully winged individuals have been taken in this country, 

 but in the West Indies and Venezuela that form is the prevail- 

 ing one. Bueno (1908b, 389) has shown that the long-winged 

 individuals of this species and Rheumatobates rileyi at times break 

 off their own elytra in order to facilitate mating. 



VI. Halobates Escholtz, 1822, 106. 



Small robust short-bodied species having the head short, 

 slightly wider across eyes than pronotum, its front portion 

 declivent ; beak awl-shaped, reaching middle of prosternum ; 

 pronotum shorter than head, transverse, its front margin con- 

 cave ; mesonotum more convex and on a higher plane than pro- 

 notum ; elytra absent ; front legs shorter and stouter than the 

 others, their tibiae slightly shorter than femora, and tarsi 

 nearly as long as tibiae, the two joints subequal in length; 

 middle and hind legs slender, longer than body, hind femora 

 longer than tibiae and tarsi united. 



The members of this genus live in large colonies on the sur- 

 face of the warm and quiet parts of the ocean, often several 

 hundred miles from the nearest land. It is, says Uhler (1884, 

 269) : 



"In the region of calms near the equator and amidst the great tracts 

 of Sargassum which float there that these creatures are most at home 

 and appear in the greatest numbers. As the patches of this sea-weed are 

 sometimes widely distributed by storms and currents, the insects oc- 

 casionally occur at long distances from their original home, even as far 

 north as the coast of North Carolina. The strands of floating sea-weed 

 furnish them a nidus for the attachment of their eggs similar to that 

 which their brethren of the fresh water find in their native streams on the 

 mainland." 



Two species are known off the coasts of North America, one 

 from our territory. 



1124 (1299). Halobates micans Escholtz, 1822, 107. 



Oval, robust. Color a nearly uniform velvety black, densely clothed 

 with a very fine leaden-gray pile; base of head and prosternum some- 



