REHN AND HEBARD 155 



ily distinguished by the more elongate stridulating field of the teg- 

 mina of semialaia. 



Tijpe. — d" ; Moss Well, Chisos Mountains, Brewster County, 

 Texas. Elevation 4500 to 5000 feet. September 5 to 8, 1912. 

 (Rehn and Hebard.) [Hebard Collection.] 



Description of Type. — Size moderately large; form compressed. Occiput 

 very considerably declivent; fastigium acute trigonal, the margins moder- 

 ately elevated, sulcate, apex acute and subdepressed, very narrowly in con- 

 tact with the frontal fastigium; eyes quite prominent, elliptical, the greatest 

 width contained about one and one-half times in the depth, the latter sub- 

 equal to that of the infra-ocular portion of the genae; antennae incomplete 

 (surpassing the tips of the wings in several specimens). Pronotum moder- 

 ately sellate, faintly buUate across the lateral lobes when seen from the dor- 

 sum, the dorsal line when seen from the side weakly elevated cephalad and 

 caudad; disk of the pronotum weakly constricted mesad, the greatest caudal 

 width of the same two-thirds the length; cephalic margin of the disk very 

 weakly arcuato-emarginate, caudal margin of disk roundly obtuse-angulate. 

 transverse sulcus forming a broad V-shaped figure on the disk; lateral lobes 

 of the pronotum with their greatest depth about two-thirds their greatest 

 dorsal length, cephalic margin slightly oblique, sinuate, ventro-cephalic 

 angle blunt obtuse, ventral margin sinuato-truncate, ventro-caudal angle 

 roundly obtuse, caudal margin oblique truncate, humeral sinus moderately 

 deep, roundly obtuse-emarginate. Tegmina elongate, failing to reach the 

 genicular extremity of the caudal femora by about the pronotal length, the 

 width at the distal fourth contained about eight times in the length of the 

 tegmina and slightly greater'than the width at the proximal third; lobate 

 marginal field equalling one-fourth the entire tegminal length, broad, costal 

 margin there strongly arcuate; apex of tegmina rather narrowly rounded; 

 stridulating field slightly longer than the disk of the pronotum, the greatest 

 width of the field (to tip of stridulating vein) about two-thirds the length of 

 the field, free margin arcuate proximad of the apex of the stridulating vein, 

 the latter well produced but rounded, distad of this vein the margin is rather 

 deepl}' sinuato-emarginate and again much less distinctly so at the apex of 

 the field, stridulating vein greatly oblique proximad and very slightly ob- 

 lique distad, anal vein nearly straight in the proximal three-fifths and ar- 

 cuate distad, speculum elongate subrectangulate; discoidal vein with four 

 rami; anterior ulnar vein reaching the sutural margin very slightly distad 

 of the middle. Exposed portion of the wings over twice the length of the 

 pronotal disk. Abdomen with the surface of the segments non-strumose at 

 the lateral pale lines, nor with the margins there produced, the margins of the 

 dorsal segments not distinctly crenulate, no process present on the proximo- 

 dorsal segment; disto-dorsal segment with the margin truncate; supra-anal 

 plate ovoid, the width distad of the base greater than at the base, the great- 

 est width subequal to the greatest length, apical margin roundly obtuse- 



TRANS. AM. ENT, SOC, XL. 



