70 Journal New York Entomological Society. [VoL xxiv, 



A STUDY OF THE SPECIES OF THE GENUS STENO- 

 PELMATUS FOUND IN THE UNITED STATES. 



By Morgan Hebard, 

 Philadelphia, Pa. 



Brief examinations of the constantly increasing series of the genus 

 in the Philadelphia collections have shown the futility of attempting 

 to apply to these, with any satisfaction, the numerous names which 

 have been proposed. Adding to these series the specimens in the 

 United States National Museum, Museum of Comparative Zoology, 

 Cornell University and other available collections, there is now be- 

 fore us sufficient material to undertake a revisionary study of the 

 forms found north of the Mexican boundary. 



Though little revisionary work of such character has been done 

 since the erection of the present genus, the number of specific names, 

 in the majority of cases based on few or unique specimens, has been 

 constantly increasing. Scudder alone appears to have had before 

 him series of any size, and his study of " The Stenopelmatins of the 

 Pacific Coast "^ is clearly superficial. 



With the undetermined material before us, we have nearly all 

 which has been recorded by Scudder, Rehn, Caudell and Bruner. As 

 a result, it is now possible to locate the specific units involved, and, 

 in the accomplishment of this task, a number of interesting facts 

 have become apparent, which should prove of decided value to sub- 

 sequent work. 



On the whole, however, the genus presents possibly the greatest 

 number of difficulties to be found in any of the North American 

 genera of Orthoptera. These may be summarized as follows : 



In the species here considered, differential genitalic characters 

 do not exist. In the males, from the nearly adult condition to matur- 

 ity, a small stout incurved chitinous hook is found on each side of 

 the supra-anal plate just proximad of the cerci (plate VII, fig. i6 ), 

 this been represented in earlier instars by a low and rounded chitinous 

 ridge- (plate VII, figs. 14 and 15). The supra-anal and subgenital 



1 Can. Ent., XXXI, pp. 113 to 117 (1899). 



2 This ridge is particularly conspicuous in the last of the instars in which 

 the subgenital plate does not wholly conceal the inner genitalia. In the sub- 



