‘4 
HUNGERFORD: AQUATIC HEMIPTERA. 203 
width on the basal %4; brownish on the apical %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 guttatipennis 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 clavus 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. 
Ambrysus 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. Elytva 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 half, except 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 posterior 
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 melanopterus Stal. 1862. 
Stal., Stet. Ent. Zeit., XXIII, p. 460. 
“Size, 11.8 mm. long; 6.7 mm. wide. A little smaller than signoreti, 
guttatipennis, and puncticollis, but differs notably from these further 
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 not entirely narrowed in front on its entire length, the posterior angles 
are right angles, a little subrounded above. The head 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 less clear, yellowish brown.’ Found in 
Texas and Arizona. 
