HUNGERFORD: AQUATIC HEMIPTERA. 203 



width on the basal % ; brownish on the apical i/4 ; segments of con- 

 nexivum brown on basal portion, yellowish behind. Transverse furrow 

 of pronotum very plain, but somewhat superficial and a little interrupted 

 at the middle; that portion of the pronotum behind the furrow very 

 pale, smooth, having the punctuation very fine, concolorous and not dense.'" 

 Reported from Colorado, New Mexico, Arizona and California. 



Ambrysus giittatipennis Stal. 1876. 



Stal., Enum. Hemip., V, p. 143. 



"Length, 13.3 mm.; width, 8.3 mm.; having the elytra darker brownish 

 chan A. signoreti, Stal., having a small discal spot and a longitudinally 

 elongated point at the middle of the corium yellowish; embolium yellowish 

 on its entire width and on its basal two-thirds; brown on apical portion; 

 entire c^avus brown except on the commissure where it is narrowly 

 yellowish; elytral margin behind the embolium obtusely sinuate; seg- 

 ments of connexivum brownish on the basal portion, yellowish behind; 

 transverse furrow on the pronotum almost lacking; posterior portion of 

 pronotum behind the furrow pale, finely scraped longitudinally, the scrap- 

 ings well visible, less so on the posterior margin where the punctuation is 

 very fine, concolorous and very dense throughout, or scrapings lacking." 

 Found in Arizona. 



Arnbrysus puncticollis Stal. 1876. 



Stal., Enum. Hemip., V. p. 143. 



"Proportionately more slender than A signoreti or A guttatipennis. 

 It is 13.7 mm. long and 8.2 mm. broad. Elytra and clavus entirely and 

 uniformly darkened, having the commissure of the clavus narrowly 

 yellowish and the embolium yellowish for its entire width on its basal 

 half, and brownish on the posterior h?lf, excent a narrow yellowish 

 border on the margin. Embolium less dilated than on the two species 

 cited above; the external border of the elytra is not sinuate behind the 

 embolium. The segments have the connexivum entirely yellowish, re- 

 markable for the very acute teeth prolonged behind from the posterioi' 

 angle of each segment. The transverse furrow of the pronotum is well 

 marked, the posterior part behind the furrow pale, smooth, without appar- 

 ent scrapings. Punctuation very fine and scarce but spread into very 

 small rather dense black points." Found in Texas and Arizona. 



Ambrysus melanopterns Stal. 1862. 



Stal., Stet. Ent. Zeit., XXIII, p. 460. 



"Size, 11.8 mm. Icng; 6.7 mm. wdde. A little smaller than signoreti. 

 guttatipennis, and puncticollis, but differs notably from these furthei' 

 by the darker coloration on the pronotum, except a narrow clear band on 

 the posterior portion by its less enlarged form and subparallel lateral 

 margins; lateral margins of pronotum strongly arcuated and in front 

 are as subparallel as their posterior portion; that is to say, the pronotum 

 is net entirely narrowed in front on its entire length, the posteinor angles- 

 are right angles, a little subrounded above. The hefd is smaller pro- 

 portionately than in the preceding species cited, the width of the pronotum 

 being proportionately equal in width, including the eyes, to that part 

 of the width of the pronotum near it and the length a little longer than 

 the width of the eyes behind. The latter are very convergent in front 

 for their entire length, surface of head and pronotum punctured, with a 

 small groove at the middle of the base of the head, having the appear- 

 ance of an anterior prolongation of the longitudinal furrow. The body 

 beneath and the legs are also les.s clear, yellowish brown." Found in 

 Texas and Arizona. 



