48 STUDIES IN AMERICAN TETTIGONIIDAE (oRTHOPTERA) 



1903. Atlanticus pachymerus Blatchley (not Decticus pachymerus Burmeister, 



1838), Orth. of Indiana, p. 393, fig. 98. [Lake, Marshall, Marion, Putnam, 



Vigo and Crawford Counties, Indiana.] 

 1907. Atlanticus pachyvierus Caudell, Proc. U. S. Nat. Mus., x.xxii, p. 323, 



fig. 28. (In part.) 

 1911. A[tlanticus\ pachymerus Walden (not Decticus pachymerus Burmeister, 



1838), Bull. 16, Conn. State Geol. and Nat. Hist. Surv., p. 141, pi. XI, 



fig. 2. [Scotland, Connecticut.] 



The name pachymerus, which has been apphecl to this species 

 by authors, has no relationship to the present form, but should 

 be used instead for a species found in the southeastern states. 

 For a discussion of this matter, see under the treatment of pachy- 

 merus. The next name available for this species is Scudder's 

 Engoniaspis testacea, described from a specimen supposed to be 

 from IVIissouri. The type of this species was in an imperfect 

 condition when described and to-day it is minus the apex and 

 greater portion of the abdomen, the cephalic and median limbs 

 and neither caudal limb is fully complete. We have been able 

 to compare it with the present series of the species of the genus 

 and it is evident, from a careful study of the proportions of the 

 pronotal disk and of the remaining limbs, that it represents this 

 species and not the allied davisi. The figure which has been 

 given of it by Caudell, while exact, is a lateral view and does not 

 bring out such features of the dorsum of the pronotum as would 

 enable one to place it properly. 



The species is readily recognized in l)oth sexes by the short 

 caudal femora, in the male sex by the relatively produced teg- 

 mina, which extend distad of the striking transverse depression 

 outlining the stridulating field a distance equal to nearly or quite 

 one-half the median length of the pronotal disk, and in the female 

 sex by the relatively short and robust ovipositor, the apex of 

 which is ventral in position. 



Type.— 9 ; Missouri? (Riley Collection.) [No. 5734, United 

 States National Museum.] 



Morphological Notes. — The principal features of variation 

 found in this species can best be treated one by one. The pro- 

 notum in the male sex always has the greatest caudal width of 

 the disk equalhng 60 to 72 per cent of the greatest length of the 

 same, while the caudal margin of the disk varies in form from 

 arcuate, to arcuate with an appreciable median flattening; the 

 cephalic margin of the disk varies in both sexes from truncate to 



