148 HEMIPTERA-HETEROPTERA. 
Apterous form. Pronotum covering: the mesonotum, the anterior lobe’ a Hittle raised and: rathor: sharply 
demarcated from the posterior lobe, the latter ferruginous.. 
¢. Anterior femora curved from the base, concave beneath, and considerably dilated towards the apex on the 
lower side; sixth ventral segment deeply emarginate at the apex. a 
Hength 84 -11,, breadth 24-33 millim. (d 9.) 
Hab. Mexico (Mus. Vind. Ces., ex coll. Signoret), Orizaba (Sallé ;. Bilimek, in Mus. 
Vind. Ces.), Cuernavaca (Bilimek, in Mus. Vind. Ces.). 
Of this species I have seen fourteen specimens, four of which are winged. This 
insect is smaller and less elongate than G. robustus, differing from it in the unarmed 
sixth connexival segment, the peculiarly formed anterior femora in the male, the 
shorter genital segments in both sexes, the ungrooved venter, &c. | | 
The specimen from the Signoret collection is labelled G. remigis, Say? An apterous 
male from Cuernavaca is figured. 
4. Gerris cariniventris, n. sp. (Tab. IX. figg. 11, ¢; lla, body from 
beneath, 3; 12, 9; 12a, body from beneath,  .) 
Winged form. Rather narrow (¢), broader (2); black, a transverse curved line at the base of the head, the 
sides of the latter before, and in some specimens between, the eyes, a median line on the anterior lobe 
of the pronotum, the lateral margins of both lobes of the pronotum, and sometimes the hind margin also, 
the pleura in great part, the cox, the eonnexival margins, and sometimes an interrupted stripe down the 
middle of the dorsal segments of the abdomen, ochraceous; ‘the under surface and rostrum (the tip 
- excepted) pale ochraceous, the mesosternum sometimes with an oblique black streak on each side extending 
backwards from the anterior coxe; the. elytra blackish or fuscous; the antenne blackish or obscure 
ferruginous, the basal joint usually paler; the posterior lobe of the pronotum sometimes obscure ferru- 
ginous behind; the legs fuscous or brownish, the anterior femora paler at the base; the upper surface 
with very short fine golden pubescence, the lower surface clothed with pallid or silvery pubescence, the 
pleura with a conspicuous stripe of silvery pubescence. Antenne rather slender, extending beyond the 
tip of the pronotum, joints 2-4 subequal in length, 1 about one-fourth longer than 2. Pronotum with 
the anterior lobe short and somewhat sharply demarcated; the posterior lobe rounded behind, flattened 
or grooved along the hind margin, transversely raised between the tumid shoulders, and more or less 
distinctly carinate down the middle. Elytra extending to considerably beyond the abdomen. Meso- 
‘pleura in the female strongly dilated before the laterally prominent intermediate coxs, narrower in the 
male. Abdomen rather short, rapidly narrowing from the base; sixth connexival segment unarmed at 
the apex; two genital segments visible from above in both sexes, the first very long in the male. 
Metasternum and venter carinate down the middle. Posterior legs with the femora considerably longer 
than the tibia and tarsus united, the first joint of the tarsi nearly three times the length of the second. 
Apterous form. Pronotum extending backwards and covering about one-third or one-half of the mesonotum, 
rounded behind ; the mesonotum ferruginous or ochraceous, sometimes with a small blackish patch in the 
middle in front divided by a pale line, and often raised or tumid behind. 
¢. Anterior femora stout, curved at the base, and subangularly dilated on the lower side a little before the 
middle ; sixth ventral segment deeply emarginate at the apex; metasternum with a stout oval prominence 
in the centre, in a line with the ventral carina. 
©. Anterior femora very feebly curved at the base; metasternum carinate, 
Length 7-10, breadth 23-31 millim. 
Hab. Mexico, Amula in Guerrero (H. H. Smith), Cuernavaca in Morelos (Bilimek, in 
Mus. Vind. Ces.); GuateMmata, near the city (Champion); Costa Rica, Volcan de Trazu, 
Rio Sucio (Rogers) ; Panama, Volcan de Chiriqui (Champion). 
