June, I9I5-] HeBARD : AMERICAN SpECIES OF MiOGRYLLUS. 103 



MIOGRYLLUS Saussure. 



1877. Grylliis, 2d Section Miogryllus Saussure, Melang. Orthopt., II, p. 362. 

 1897. Miogrylhis Saussure, Biol. Cent.-Amer., Ortli. I, p. 227. 

 1901. Miogrylhis Scudder, Psyche, IX, p. 256. 



The genus included five species. Genotype. — Miogryllus pusillus 

 [Grlyllns'] pusillus] (Burmeister)= Aliogryllus convoliitus [Gryllus 

 convoliitus'] (Johannson), selected by Kirby, 1906. 



This genus includes a number of species which are closely related 

 to the genus Gryllus and for which no definite single differential 

 characters exist, excepting the form of the titillatores (a portion of 

 the male genitalia concealed within the subgenital plate), and in the 

 proportions of the wings; in the long-winged condition, wings which 

 are proportionately much longer than the tegmina (in Miogrylhis, 

 23^ to 3^ times the tegminal length, in Gryllus, in the majority of 

 species normally 1^-2 times this length but in a few species 2 or 

 slightly more than 2 times the tegminal length), while in material 

 having the wings greatly reduced and hidden by the tegmina, these 

 organs are perfect though greatly reduced in Gryllus, but small pad- 

 like appendages in the present genus. All of the species average 

 smaller than do the American forms of Gryllus and have the spines 

 of the dorsal margins of the caudal tibiae, in the great majority of 

 specimens, 4 or 5 in number (this being fewer than is normal in 

 Gryllus), less heavy and not as rigidly fixed in their sockets as in 

 that genus. The male tegmina have normally 2, but occasionally i 

 or 3, transverse veins (in Gryllus the number is normally 4 or 5, 

 rarely 3 or 6). The male titillatores are formed by two dark chiti- 

 nous perpendicular plates which are uncinate dorsad, between the 

 dorsal margins of which are two small acicular projections of equal 

 length. In the American forms of Gryllus the medio-dorsal portion 

 of this organ is produced in a large horizontal triangular plate with 

 apex curved upward. The species agree with those of Gryllus in 

 having a large membranous foramen on the outer face of the cephalic 

 tibicC and also a smaller but distinct membranous foramen on the 

 inner face of the same, excepting in micropterous individuals where 

 this inner foramen is frequently greatly reduced or absent on one 

 limb or both. 



History. — No species have been incorrectly referred to the present 



