394 PROCEEDINGS OF THE ACADEMY OF [June, 



A REVISION OF THE SPECIES OF THE GENUS NEMOBITJS (ORTHOPTERA . 



GRYLLID^) FOUND IN NORTH AMERICA NORTH OF 



THE ISTHMUS OF PANAMA. 



BY MORGAN HEBARD. 



The genus Nemohius is typical of the group Nemobiites, the other 

 genera of which are more or less aberrant. The group Nemobiites 

 stands at the head of the subfamily Gryllinae, which is the second 

 division of the family Grylhdse. 



All of the species of Nemohius are of small size and are rather 

 delicate in structure; their bodies are covered with long hairs. The 

 plasticity in certain species, the lack of characters in the male 

 genitalia and the great variability in size, wing length, and coloration, 

 all combine to make the study of the genus difficult. Added to this, 

 the many incorrect determinations and frequent synonyms have 

 caused the task of correcting the nomenclature to be unusually 

 complex. An effort is made in the present paper to afford sufficient 

 information for subsequent workers to be able satisfactorily to 

 determine material of either sex, but it is certain that, especially 

 in the males of some species, no single specific character can be 

 considered absolutely trustworthy, and careful consideration of all 

 the specific differences must be made before a safe conclusion can be 

 reached. The large series of different species before us show con- 

 clusively that, where some character may be safely relied upon in a 

 large series of the same species from one region, that character is 

 often obscure or unreliable in series from other portions of the insects 

 range and in consequence can only be used to supplement the com- 

 bination of characters found in that species. 



Genus NEMOBIUS Serville. 



1839. Nemohius Serville, Hist. Nat. Ins., Orth., p. 34.5. [Generic de- 

 scription.] 



1869. Argizala Walker, Cat. Dermap. Saltat. Br. Mus., I, p. 60. [Generic 

 description.] 



1874. Nemohius Saussure, Miss. Sci. Mex., Rech. Zool., VI, p. 380. [Key- 

 to American species and descriptions of new species.] 



1877. Nemohius Saussure, Melang. Orth., II, Fasc. V, p. 236. [Full 

 generic description, key to species of the world and many descriptions of 

 new species.] 



