394 NEW NORTH AMERICAN MELANOPLI (oRTHOPTERA) 



It is of interest to note that an intermediate condition occurs in 

 material from Polk County, Wisconsin, showing nearer agreement 

 with typical viridipes; while the males before us from Ann Arbor, 

 Michigan, are also intermediates, referable to v. eurycercus, but 

 showing distinct variation toward v. viridipes. In Indiana, how- 

 ever, the area of intergradation between the races is best dem- 

 onstrated, as Blatchley has taken material of the species from 

 a large number of localities. In the material before us from that 

 state, males from Vigo and Tippecanoe Counties are typical 

 V. viridipes; one from Fountain County and one from Vigo County 

 are slightly atypical v. viridipes; intermediates are from Vigo and 

 Lake Counties, while males from Fountain and Marion Counties 

 are typical v. eurycercus. 



It is apparent that the races intergrade in Indiana over the 

 western section of the state, a certain amount of interdigitation 

 occurring, v. viridipes sometimes pushing in from the west and 

 V. eurycercus from the east. 



Type. — d^ ; Derrick City, McKean County, Pennsylvania. 

 June 6, 1915. (Wm. T. Davis.) [Hebard Collection, Type no. 

 563.] 



Agrees closely with p. viridipes, differing only in the form of the cerci.^^ 

 Cerci moderately stout, curved inward distad, approximately twice as long 

 as basal width, lateral margins almost straight and very feebly convergent to 

 distal third, where the convergence becomes stronger to the broadlj- roimded 

 apex; external surface of distal third showing a weak longitudinal depression. 



Allotype. — 9 ; same data as type. [Hebard Collection.] 

 This sex can not be distinguished from females of v. viridipes. 

 In the regions where the races interdigitate, males taken at the 

 same time as the females are necessary for determination. 



31 As described by Scudder (Proc. U. S. Nat. Mus., xx, p. 256, (1897)). 

 Blatchley's first description of the cercus of viridipes (Orth. of Indiana, p. 

 305, (1903)) is apparently drawn from intermediate material which he had 

 before him. 



