SITALCES. 291 



[SITALCES, St&l. 

 Sitalces, St&l, Bihang till K, Svensk. Vet.-Akad. Handl. v. no. 9, p. 16 (1878) ; Obs. Orthopt. iii. 

 p. 16 (1878) ; Giglio-Tos, Boll. Mus. Zool. Anat. Comp. Univ. Torino, xiii. no. 311, p. 48 



(1898). 



The genus Sitalces, Stal, which is related to Ommatolampis, Burm., is composed of 

 rather small to medium-sized locusts, which are either apterous or have the tegmina 

 extremely rudimentary. In general colour the species thus far described are largely 

 olivaceous or greenish-testaceous varied with ferruginous, browns, and black. The 

 genus belongs to Tropical America, and especially to Middle and Northern South 

 America, and it almost certainly extends to Panama. The annexed synoptic table will 

 aid the student in determining the ten species already known or that are now at hand. 



Stal's 8. volxemi may be considered the type of the genus. 



Synopsis of the Species of Sitalces. 



A 1 . Larger species (length, ? ? , 18-23 mm.). Hind tibiae furnished with 

 7 or 8 spines on the outer carina. 

 b\ Tympanum or auditory apparatus obsolete or subobsolete. 



c 1 . Tubercle of the prosternum very obtuse, only slightly elevated, the 

 apex armed with an erect spine. 

 d x . Smaller (length, $ 14, $ 20 mm.). General colour olivaceous- 

 green. Median carina of the pronotum subobliterated . . . volxemi, Stal. 

 d 2 . Larger (length, $ 15, $23 mm.). General colour brownish-olive. 



Median carina of the pronotum well-defined throughout. [Brazil.] robustus, Bruner. 

 c 2 . Tubercle of the prosternum more elevated, pyramidal or acuminate, 



without the erect spine. Apterous. [Venezuela.] 1. coxalis, Stal. 



b 2 . Tympanum or auditory apparatus apparent, nearly or quite normal. 



c 1 . Hind tibiae 7-spined externally vittiventris, Stal. 



c 2 . Hind tibias 8-spined. 



d 1 . Face almost impunctate. [Isl. of Trinidad.] 3. trinitatis, Bruner. 



d 2 . Face distinctly punctate. [Venezuela.] 2. punctifrons, Stal. 



A 2 . Smaller species (length, ? $ , 14-15 mm.). Hind tibiae provided with 

 but six spines in the outer row. 

 b l . Tegmina wanting. Apex of hind femora inf uscated. [Santarem] . nudus, sp. n. 

 b 2 . Tegmina present. Hind femora at most with a dark preegenicular 

 annulus. 

 c\ Tegmina narrow, at least four times as long as broad, bicoloured, 



extending beyond the apex of metathorax. [Brazil ?] .... varipennis, sp. n. 

 c 2 . Tegmina broader, suboval, about twice as long as extreme width, 

 scarcely reaching the middle of metathorax. 

 d 1 . Median carina of pronotum but little interrupted by the transverse 



sulci; dorsum plainly vittate with flavous. [Brit. Guiana.] . . 4. ovatipennis, sp. n. 

 d 2 . Median carina widely interrupted by the transverse sulci ; dorsum 



almost uniformly infuscated. [Chapada, Brazil.] infuscatus, sp. n. 



2Pp2 



