136 ORTHOPTEROUS GROUP INSARAE 



tuberculate. Cephalic margin of the pronotal disk with or without 

 a median tubercle, this generally absent in northern specimens and 

 almost always present in southern (from Victoria and Beeville 

 south) individuals. The proximo-dorsal abdominal process of the 

 male is almost always lower than in the typical form and never 

 bulbous in character. The cerci of the male exhibit a gradual nar- 

 rowing of the distal portion when specimens from Nebraska south 

 to southern Texas are examined, the Niobrara, Nebraska and Bar- 

 ber County, Kansas individuals having the recurved section as 

 sharply bent as in gracilipes, broad and sublamellate, with the im- 

 mediate apex not at all attenuate and with the main shaft thick- 

 ened, from which type there is a gradual drawing out of the append- 

 age, until in the material from southern Texas the cerci are as 

 given in the description of this race, the exact angle of the bend of 

 the distal fourth varying somewhat, but the shaft slenderer and 

 the form tapering with the apex aciculate. On the other hand the 

 single Tonala individual has the cerci broader, the distal section 

 much depressed and lamellate, the general form much as in the 

 specimens from western Texas referred to true gracilipes. The 

 form of the subgenital plate of the male varies as in the typical 

 form. 



Remarks. — The race to which the name constrida is restricted, 

 is a unit exhibiting within itself considerable variation, this in size 

 and to a less extent in structure, but as a whole it shows less plas- 

 ticity than A. gracilipes s.s. The differentiation of the material 

 of the two races is not difficult and, we feel, completely warranted 

 by the series before us. 



Specimens Examined: 70; 42 cf', 27 9 , 1 immature 9 : 



Niobrara, Knox County, Nebraska, August 2, 1902, (W. D. Pierce), 2 cf, 

 [Univ. of Nebraska]. 



Clark County, Kansas, elevation 1950 feet, August 25, 1911, (F. X. Wil- 

 liams), 1 d^, [Univ. of Kansas]. 



Barber County, Kansas, (F. W. Cragin), 2 cf, 2 9 , [Hebard Collection ex 

 Bruner]. 



Wichita, Sedgwick County, Kansas, June 11, 1909, (F. B. Isely), 1 c^, 

 [Univ. of Kansas]; July 13 to 20, 1 d^, 1 9 , [U.S.N.M.]. 



Kansas, 1 o^, [U.S.N.M.]. 



Dallas, Texas, 1 9 , [U.S.N.M.]; September 25 and 26, 1912, (R. & H.), 1 9 . 



Weatherford, Parker County, Texas, elevation 1000 to 1100 feet, Septem- 

 ber 23, 1912, (R. &H.), 1 9. 



