hungerford: aquatic hemiptera. 189 



anterior surface. The middle tarsus has an irregular row on lower 

 posterior margin and a definite row of four spines on the upper. Tarsal 

 claws unequal as before. Hind legs as in the other instar in general 

 equipment, posterior margin of hind femur with a row of about 30 short 

 spines of nearly equal length, the distal pair being a little stronger than 

 the others, and close together. Three spines mark the distal ventral 

 margin of the femur. The hind tibia possess tibial combs each in tw'o 

 groups, one consisting of four stout spines, and the other of three. 



Dorsal Vieic. The wing-pads of mesothorax extend back more than 

 one-half the length of the margin of mesothorax and metathorax taken 

 together. 



Fifth Instar. 



Size. Length, 10.6 mm.; width of body, 5.1 mm.; width of head, 2.86 

 mm.; distance between eyes at vertex, .936 mm.; distance between eyes 

 at narrowest point, .52 mm. 



Color. In dorsal view, eyes dark red, thorax white with greenish tinge; 

 prothorax with a smoky band near each lateral margin and parallel with 

 it. Postero-lateral angle smoky. Mesothoracic "ning-pad with two longi- 

 tudinal smoky bands joined posteriorly by the dark band of the apical 

 margin. Posterior margin of metathorax marked by a smoky line that 

 diffuses into a band at lateral margins. The abdomen is chalky white, 

 strongly marked by transverse bands and spots of smoky black. Basal 

 portion of abdomen is crossed by three rather wide bands. The following 

 two bands are broken on the dorsum, but the two caudal transverse bands 

 are broad and hea\'>'. 



In ventral view, a median dark band divides the head longitudinally. 

 The base of the beak and beak dark; limbs testaceous, equipped with 

 black hairs, and femora with longitudinal stripes of darker color; con- 

 nexivum with six pairs of dark rectangular spots; guard hairs dark. 



Structural Peculiarities. Ventral view, median abdominal carina long, 

 in three sections and extending nearly the length of abdomen ; front 

 femur with 4 strong spines on upper margin of posterior side; tibia, 6 

 spines on either edge; tarsus as in 4th instar. Middle femur now has, 

 besides this clump of spines on the tubercle, four other spines and the 

 spur, which is now longer than in previous instar. Posterior margin of 

 hind femur with about 44 short spines plus three longer ones at distal 

 end. Distal ventral margin of femur with five strong spines. Tibia with 

 distal ventral margin equipped with two sets of four or five strong spines. 



Dorsal view: Wing-pads extend back to abdomen in this instar. 



Sximmary. This bug has been reported from New York. It prefers 

 clear waters where it frequents the shelter of shaded places. The eggs 

 are placed in the tissues of aquatic plants instead of upon the plant as is 

 the case with the other members of the genus. Egg laying begins in May 

 and the adults of the first generation come to the adult stage in mid July 

 in New York. There is insufficient evidence to state whether a second 

 generation appears. 



