MESOCHLOA.— SILVITETTIX. 55 



l. Mesochloa abortiva, Bruner. 



Eritettix abortivus, Bruner, Proc. U.S. Nat. Mus. xii. pp. 56, 57, t. 1. figg. 8, 9 1 ; McNeill, Proc. 



Dav. Acad. Nat. Sci. vi. p. 220 \ 

 Mesochloa abortiva, Scudd. Psyche, viii. p. 239 3 . 



Hab. North America, Texas 1-3 . 



While this insect is not represented in any of the collections examined from south of 

 the Rio Grande, it is exceedingly common in portions of South Central Texas, and no 

 doubt occurs in similar localities across the line in Mexico.] 



SILVITETTIX, gen. nov.* 



Of medium size, the wings strongly abbreviated in both sexes. Head and pronotum rugose and coarsely 

 punctulate. Antennae with the joints a little flattened, in the female about equalling the combined length 

 of the head and pronotum, in the male as long as or longer than the hind femora. Face strongly oblique ; 

 vertex well advanced in front of the eyes, the sides slightly rounded and provided with rather high carinae, 

 the disc sulcate, furnished with a median carina which continues over the occiput to the front edge of 

 the pronotum, this carina generally accompanied from slightly in front of the eyes by well-marked supple- 

 mentary carinas. Pronotum scarcely constricted at the middle, the hind edge slightly widest ; median 

 carina not prominent, but equal throughout, cut back of the middle by the last transverse sulcus ; lateral 

 carinas blunt, strongly approaching in the centre ; anterior edge above squarely truncate, the hind margin 

 subangulate ; sides rather deep, the lower margin sinuate, dropping lowest immediately over the base of 

 the front legs. Tegmina rather coarsely veined and with the scapular area dilated. Hind femora 

 moderately robust, in the males greatly surpassing, in the females just about reaching, the tip of the 

 abdomen. Tibiae with 9 or 10 spines in the outer row, and with the inner apical spurs subequal. Valves 

 of ovipositor rather stout and protruding. The tip of the abdomen of the male blunt ; the last ventral 

 segment short and acuminate ; supra-anal plate plain and triangular, a little tumid in the middle near 

 the base. 



wings slightly surpassing the abdomen and surpassed by the hind femora, which are moderately slender 

 and compressed." 



This genus has much the general aspect of Amphitornus, but has prominent lateral carinae on the pronotum 

 and supplementary carinae on the head ; the supplementary carinae of the pronotum approach the median 

 carina much more nearly than in Eritettix, from which it differs by its non-clavate antennae. 



l. Eupedetes carinatus, Scudd. 



Eupedetes carinatus, Scudd. Proc. Dav. Acad. Nat. Sci. ix. p. 25, t. 1. fig. 2 \ 



" Testaceous, feebly marked with fuscous, beneath flavescent. Head with a broad longitudinal light fuscous 

 stripe behind upper portion of the eyes, with one or two faint lines behind the eyes below it ; antennae 

 flavo-testaceous ; median carina of vertex heaviest in front and especially in the fastigium, which the 

 supplementary carinae do not enter. Pronotum testaceous, the lateral carinae marking the outer limit of 

 a light fuscous stripe ; supplementary carinae of pronotum less prominent than the median carina ; lateral 

 lobes with a slightly oblique, fuscous -edged, luteous stripe on the lower part of the metazona. Tegmina 

 testaceous, flecked with fuscous mesially. Hind femora flavo-testaceous, faintly infuscated above ; hind 

 tibia? flavous, with 10-11 black spines on either margin." 

 Length of body, 6 , 14*5, of antennae 5-5, of pronotum 3, of tegmina 10-5, of hind femora 10 millim. 

 Hab. North America, La Trementina, New Mexico (Miss Alice Blake, *). 

 One male. Is this not Eritettix variabilis, Bruner ? 



* An addition to the genera characterized in the Synopsis (anted, pp. 26-34). 



