1048 FAMILY XXXIX. — NOTONECTID^E. 



Vigo and Posey counties, Ind., October. Ormond, Sanford, 

 Istokpoga, Arch Creek, R. P. Park, Dunedin and Ft. Myers, 

 Fla., December — April (W.S.B.). Raleigh, N. Car., March- 

 August (Brimley). Sherborn, Mass., April 11 (Frost). Its 

 known range is more southern than that of flwninea, extending 

 from Massachusetts southwest in the coastwise states to Louis- 

 iana and Texas. Known also from Kansas. The southern In- 

 diana records above given are the only ones known from the 

 interior, and the specimens were taken from ponds in the 

 Wabash River bottoms, the fauna and flora of the Austrori- 

 parian Life Zone extending along the stream to Vigo County. 

 This is the largest of our eastern species and is readily dis- 

 tinguished from fluminea by the characters given in key. 



1187 (1401). Belostoma testaceum (Leidy) , 1847, 60. 



Broadly oval. Color ranging from a nearly uniform pale brownish- 

 yellow to dark fuscous-brown ; legs dull yellow, irregularly barred or 

 spotted with fuscous; under surface in great part fuscous, the sides of 

 ventrals paler. Head short, obtuse. Other characters as in fluminea. 

 Length, 14 — 18 mm. 



Dunedin, LaBelle, Moore Haven and R. P. Park, Fla., Dec. 

 12 — April 8. Recorded also from Titusville, that State. Raleigh, 

 N. Car., August — October (Brimley). Mobile, Ala., January — 

 March (Gerhard). Ranges from New York west to Michigan 

 and southwest to Florida and Texas. The Florida specimens at 

 hand are all much darker than those from North Carolina, their 

 hue being perhaps due to the coffee-colored surface waters of 

 the ponds and lakes in the saw palmetto regions of the former 

 State. 



Family XXXIX. NOTONECTID^E Leach, 1815, 124. 



The Back-swimmers. 



Small or medium sized aquatic Heteroptera, so named be- 

 cause the upper surface is convex and obtusely keeled, thus 

 enabling them to easily swim back downward. They have the 

 vertex narrow, fitted wedge-shaped between the large, elongate 

 and prominent eyes, front of head subvertical, hind one in- 

 serted in thorax to eyes and overlapped by the front of prono- 

 tum ; ocelli absent ; antenna? very short, 3- or 4-jointed, con- 

 cealed in a cleft beneath the eyes ; beak 3 or 4-jointed, short, 

 stout, awl-shaped, its apex in repose resting in a groove on 

 front of mesosternum ; pronotum subtrapezoidal, convex, its 



