310 PROCEEDINGS OF THE ACADEMY OF [May, 



horizontal, much shorter than in the female, hardly more than half 

 the length of the eye, apex very blunt; eyes very prominent, ovate 

 in outline, their length more than half that of the proximal portion 

 of the dorsum of the head; antennae slightly longer than the eye^ 

 five-jointed. Pronotum subcylindrical, subequal in width except 

 for the expansion at the cephalic margin and the insertion of the 

 cephalic limbs, the former margin truncate mesad with a pair of low 

 flanking tubercles and obliquely truncate laterad; width at the 

 insertion of the cephalic limbs contained two and one-half times in 

 the length of the pronotum, caudal margin non-tuberculate; surface 

 of the dorsum without the prominent ridges found in the female. 

 No tegmina or wings present. Caudal margin of the mesonotum 

 non-tuberculate. Abdomen with the medio-longitudinal carina 

 indicated only caudad; supra-anal plate sublanceolate, apex well 

 rounded, a prominent medio-longitudinal sulcus present on the 

 proximal two-thirds; cerci simple, styliform, short, blunt; subgenital 

 plate moderately rostrate, subacute, carinate ventrad, dorsal face 

 of the apex flattened, sulcate, the apical margin slightly cleft. Limbs 

 slightly more robust than in the female; caudal femora slightly more 

 bullate, the tips of the femora reaching to the distal margin of the 

 sixth abdominal segment. 



Measurements. 



Length of body 40 . mm. 



Length of pronotum 8.3 " 



Greatest width of the pronotum at the insertion of the 



cephalic limbs 3 . 



Length of remaining thoracic segments 6 . 



Length of cephalic femur 7.3 



Length of median femur 7 . 



Length of caudal femur 15.5 



The only information with the specimens on the habits of the 

 species is on several Mendoza individuals labelled ''On Larrea." This 

 is apparently Covillea (Larrea of authors) divaricata, a shrub which Mr. 

 Jorgensen tells us constitutes an important part of the vegetation of 

 the Mendoza region. It is probable that the insect spends a con- 

 siderable part of its life on the twigs of the bush, which it simulates 

 very well and where it would be well protected. This proclivity is 

 found in certain species of Orthoptera occurring on the allied C 

 tridentata of the Lower Sonoran deserts of North America. 



Nine of the pairs in the series were taken "in copula." The 

 earliest seasonal date that is represented by adults is November 15, 



