1913.] NATURAL SCIENCES OF PHILADELPHIA. 395 



1896. Nemobius Scudder, Jour. N. Y. Ent. Soc, IV, p. 99. [Key to North 

 American species and descriptions of new species.] 



1896. Noyiobius Pantel, Anal. Soc. Espan. Hist. Nat., XXV, p. 47. [Mor- 

 phological studies.] 



1896. Nemobius Scudder, Psyche, VII, p. 431. [Key to North American 

 species and descriptions of new species.] 



1897. Nemobius Saussure, Biol. Cent. Amer., Orth., I, p. 221. [Key to 

 Central American species and descriptions of new species.] 



1900. Nemobius Blatchley, Psyche, IX, p. 51. [The Indiana species with 

 descriptions of new species.] 



1903. Nemobius Blatchley, Orth. of Indiana, p. 419. [Numerous notes 

 and description of one new species.] 



1904. Nemobius E. M. Walker, Can. Ent., XXXVI, p. 181. [Numerous 

 notes and descriptions of new species.] 



1906. Nemobius Kirby, Synon. Catal. Orth., II, p. 13. [List of species.] 



The genus included two species. Genotype — Nemobius {Nevio- 

 hius) sylvestris [Acheta sylvestris] (Bosc), selected by Kirby, 1906. 



Generic Description.— ^ize small; form compact; body pub.escent 

 and sparsely clothed with long chsetiform hairs. Head rounded, 

 a little flattened in front; interantennal protuberance feeble, obtuse 

 and rather large; eyes oval, rather protuberant; maxillary palpi 

 with distal extremity of terminal joint very moderately oblique. 

 Pronotum a little wider cephalad than the head; lateral lobes with 

 ventral margin horizontal, the ventro-cephalic and ventro-caudal 

 angles projecting about the same and similarly rounded. Tegmina 

 complete or abbreviate; in the male furnished with a rather simple 

 tambourine, having only a single ulnar (oblique) vein which is longitud- 

 inal, lengthened, developing from the angle of the stridulating (anal) 

 vein; in the female the dorsal field is furnished with few but promi- 

 nent longitudinal veins connected by transverse veinlets which are 

 directed at right angles to the veins; the tegmina are always present 

 in the North American species and are rounded at the apex; lateral 

 field of tegmina occupied by five or six simple veins which are free 

 from their bases. Wings strongly developed, abbreviate or absent. 

 Ovipositor slender, long and straight, or shorter and very gently 

 arcuate; apex very little enlarged, in all of the North American 

 species the portion formed by the dorsal valves is armed with serra- 

 tions or serrulations, the portion formed by the ventral valves is 

 unarmed or supplied with minute, very widely spaced serrulations. 

 Cerci of both sexes moderately long, tapering, and covered with 

 hairs. Cephalic tibiae supplied with a few long slender hairs, caudal 

 face only bearing a distinct tympanum, corresponding portion of 

 cephalic face slightly swollen. Caudal femora greatly dilated; 

 caudal tibiae with dorsal margin armed with a double row of extremely 

 long, widely spaced, mobile spines (in the North American species, 



