JfO Bulletin No. 159 



Two small, blackish species were rather common in 

 Straight Creek and in the Cumberland River at Pineville. 

 The commonest one is represented by figure 35. It is with- 

 out wings, and rows itself about with such rapidity that it 

 is not easily captured. On each of its middle feet is a fan 

 composed of feathered hairs which are caught and held 

 expanded by a claw of the split tarsus. This fan appears to 

 dip beneath the surface when in use and gives its possessor 

 a purchase on the water much like that obtained by a boat- 

 man with an oar. 



Rhagovelia obesa, Uhler. — At the edges of the creeks 

 and of Cumberland River small schools of these water 

 striders, so-called, were often observed. They were es- 

 pecially common near Cary in Straight Creek and in the gap 

 of Pine Mountain along the rapids of the river. They gen- 

 erally stayed in the sheltered places about submerged rocks 

 in the larger stream, but are surprisingly quick in escaping 

 the collector's net, and are quite able to care for themselves 

 under any circumstances likely to arise in the swift current. 

 These little insects are provided with a jointed beak and 

 prey upon other insects which fall upon the water. 



Length 3.2—3.3 mm. Division of body following the 

 head widest. Front of head nearly even with the rounded 

 eyes. Legs long, slender, the middle pair longest and 

 bearing a fan-shaped tuft of plumose hairs (lacking in 

 the young), kept expanded by claws of the tarsus. Last 

 tarsal segment long, split. Abdomen of the male with 

 straight carinas along the margins of the abdominal somites 

 terminating abruptly at the sides near the tip without 

 meeting. In the female ridges originate at the sides of 

 the thorax, thence curve backward and inward extending 

 along the dorsum of the abdomen and meeting behind. 

 Posterior femora of male noticeably thickened, and bearing 

 behind a spine followed outwardly by a series of small denti- 

 cles. In the female the large spine alone is present and the 

 femora are not thickened. Both sexes are wingless in all 

 examples collected. Color black. Antennas and legs whitish 

 at bases. A pair of transverse yellow spots on the dorsal 



