1919.] NATURAL SCIENCES OF PHILADELPHIA. 105 



Lenp:th of Length of Length of Length of 

 body. pronotum. tegnien. caudal femur. 



Sycamore Wash, Arizona 49.8 7.8 34.5 26.4 



Riovillc, Nevada 50 8 36 22 



Atypical 



Dallas, Texas 41 6.7 28.9 24.7 



Dallas, Texas 48.5 8.1 37 30 



Mountain Park, Oklahoma 47.5 7.9 34.9 28.5 



From the above measurements it is evident there is a very great 

 amount of individual size variation, while at the same time there 

 is a certain amount of geographic correlation of this feature. The 

 maximum sized specimens are from two regions — one, the south- 

 central portion of Texas; the other, the Rio Colorado region of 

 southern Nevada (Rioville). As we have but a single pair from 

 the latter region, this condition may not be supported in a more 

 extensive representation. The species, as well as the race, is, 

 however, distinctly at its maximum size in the mesquite region 

 of south and south-central Texas, west to the vicinity of Carrizo 

 Springs. The minimum sized individuals are from the Rio Grande 

 region of New Mexico and western Texas, these belonging to the 

 markedly attenuate condition found in that region and discussed 

 under ''Morphological Notes." The atypical specimens from 

 northern and north-central Texas (Dallas and Hearne) are under 

 the average size for the form. 



Color Notes. — The pattern variation in this form covers prac- 

 tically the whole gamut of such fluctuation as found in the genus, 

 the combination of these tendencies or "unit characters" being 

 much the same as in the other species, but the apparent strength 

 of the pattern is very greatly altered by general tonal modifica- 

 tions, which probably are I'esponses to environmental conditions. 

 The relative intensity of the paired cephalic and pronotal post- 

 ocular bars; the relatively solid coloration or maculate condition 

 of the discoidal field of the tegmina, especially in the female sex; 

 the contrast of the pale subcostal line on the tegmina ; the strength, 

 width and continuity of the median dark line on the head and 

 pronotum, and the presence, and intensity and solidity when 

 present, of dark barring on the dorsum of the caudal femora, as 

 well as the depth of the coloration of the caudal tibiae, are all 

 features which, in a series as large as the present one, show kaleido- 

 scopic variation. Of these there appears to be some geographic 

 correlation in the extent to which the blackish of the postocular 

 bars extends upon the dorsum of the pronotum. In material 

 from central and southern Texas this is usual and more extensive 



