to 
ASSES @qypptge cc ct 145 
‘a; Antenne with joint l“hearly or quite as long as 2 and 3 united; anterior 
femora almost straight in the §: pronotum covering the mesonotum in 
the. apterous form. [Hycrorrecuvs, Stal.] | 
a'. Outer apical angles of the sixth connexival segment produced into a 
short spine; venter in the ¢ rather deeply sulcate and with a double 
- series of black spots . . . . .. . see » 2 « « remigis, Say. 
: 8. Outer apical angles of the sixth connexival segment produced into a 
long acute spine in the ¢, and with a shorter spine in the ¢ ; venter 
in the ¢ shallowly suleate and with a double series of indistinct 
darker spots. . 6. 2. 6 ee ee ee we ew ew we ~ «Obustus, Ubler. 
6. Antenne with joint 1 much shorter than 2 and 3 united; outer apical 
angles of the sixth connexival segment not produced into a spine ; 
anterior femora curved in the ¢. - [ Limnorrecuvs, Stal.] 
c’. Venter and metasternum more or less distinctly carinate in both sexes ; 
abdomen with the first genital segment long in the ¢. 
a, Metasternum simply carinate, and the anterior femora dilated 
towards the apex on the lower side, in the ¢: pronotum covering 
the mesonotum in the apterousform . . . . . . . . « mewicanus, n. sp. 
_ 6", Metasternum with a stout oblong prominence, and the anterior 
femora subangularly dilated on the lower side a little before the 
middle, in the ¢: pronotum extending over the anterior portion 
only of the mesonotum in the apterous form . . . . . . « cariniventris, n. sp. 
d', Venter and metasternum neither carinate nor sulcate; abdomen short, 
with the first genital segment short in the ¢; anterior femora not | 
dilated on the lower side: pronotum not extending over the meso- 
notum in the apterous form. « - 6 6 ee ee ees . flavolineatus, n. + §P. 
1. Gerris remigis, — 
‘Gerris remigis, Say, Descr. of New Species of Hemipt. Heteropt. of N. Am. (New Harmony, 
. Dec. 1831)’; Complete Writings, i, p. 362.?. 
Hygrotrechus remigis, Uhler, Bull. U. S. Geol. and Geogr. Surv. i. ser. 2, Pe 335, t. 21. fig. 40 
(1876) °; Kingsley’s Stand. Nat. Hist. ii. p. 267, fig. 322 *. 
. Winged form. Robust, elongate, the head, the anterior lobe of thé pronotum, and the pleura black, the head 
with a transverse curved line at the base and the anterior-lobe of the pronotum with a median line, and 
‘sometimes the lateral margins also, ochreous or ferruginous ; the posterior portion of the pronotum and the 
elytra usually brownish-ferruginous, sometimes blackish-brown; the abdomen blackish above, with the 
connexivum and terminal segments more or less ferruginous, with indications of a black stripe down the 
middle, interrupted by an elongate greyish mark on each segment; meso- and metasternum blackish, 
each with a space in front of the coxee ochreous or ferruginous ; venter ferruginous or flavo-ferruginous— 
' } i the-male with a broad blackish space down the middle, interrupted by a pale median line (forming two 
large spots on each segment), the sides also more or less. blackish,—in the female with a narrow median 
stripe, interrupted by a pale central. ling, and the sides towards the base, blackish; the antenne blackish, 
sometimes with joints 1 or 1 and 2 obscure ferruginous ; ‘the legs brownish or brownish- -ferruginous, the 
i ““-antefior femora paler at the'base,the-antérior tibie: and-tarsi usually blackish ; the upper surface clothed 
ics awith: a ‘very short fine golden or greyish’ pubescence; ‘the ‘elytra: with oblong thickly pubescent patches on 
the nervures, the connexival segments usually with a narrow silvery- or golden-pubescent patch in front ; 
BIOL. CENTR.-AMER., Rhynch., Vol. II., August 1898. 19 
