MORGAN HEBARD 161 



Sufficient individual variation occurs in the cerci to lead to 

 possible incorrect determinations or the supposition that a dis- 

 tinct race or even species might be represented by certain indi- 

 viduals. This is true for all the species of which I have large 

 series but particularly so for islandicus and celatus, in both of 

 which species incipient racial differentiation is strongly suggested. 

 The species of the Mancus Group are, therefore, much more 

 conclusively distinguished by the characters shown by the penis, 

 which are much more constant. 



Melanoplus mancus (Smith) (PI. XI, figs. 1 and 2.) 



1868. Pezotettix mancus Smith, Proc. Portland Soc. Nat. Hist., I, p. 149. 



[ $ , 9 ; Speckled Mountain, near Stoneham, Maine.] 

 1920. Melanoplus mancus Morse, Orth. of New England, p. 518, pi. 22, 



figs. 28 to 31, pi. 23, figs. 9 and 10. 



This boreal species is probably widespread in southeastern 

 Canada, but is as yet known there only from the series here 

 recorded. It is widespread in favorable environment in the 

 northern portion of the eastern United States and reaches south 

 in the Appalachian Mountains as far as central Virginia. 



The species shows little variation. Only the apices of the male 

 cerci vary individually from feebly elongate spatulate to scarcely 

 at all spatulate, the margins there frequently slightly irregular 

 in curvature and the external surface sometimes weakly dimpled. 

 The large series now available prove to my satisfaction that not 

 even incipient racial differentiation is indicated anywhere in the 

 range of mancus. 



The related islandicus Blatchley was placed as a western race 

 of mancus by me in 1932, such being strongly suggested by all 

 external characters but now known to have been a false conclu- 

 sion, as the form of the penis in islandicus is constant and widely 

 distinct. The new species, serrulatus, from the mountains of 

 western North Carolina, might just as easily have been confused 

 with mancus had the even more distinctive development of the 

 penis not been observed. 



The following material is before me: 



Quebec: Lac Sainte Marie, IX, 5, 1935, (F. A. Urquhart), 6$, 2$, [Can. 

 Nat. and Hebard Cms.]. 



TRANS. AMER. ENT. SOC, LXIU. 



