MORGAN HEBARD 23I 



Specimens Examined: 68; 27 males, 18 females, 10 immature males and 13 

 immature females. 



Kits Peak Rincon, Baboquivari Mountains, Arizona, about 4050 feet, \'III, 

 I to 4, 1916, (Lutz and Rehn), 2 d' , [A. M. X. H. and A. X. S. P.]. 



San Lorenzo, Coahuila, Mexico,' V, (E. Palmer), 2 0^,8 9, [M. C. Z., Hebard 

 Cln. and A. X. S. P.]. 



San Pedro, Lower California, Mex., 1893, i d^, [Hebard Cln.]. 



Sierra El Tosti, L. Cal., Mex., X, 1893, (G. Eisen), 3 d^, 5 9.3 juv. d", 4 juv. 9 , 

 [Cal. Acad. Sci., Hebard Cln. and A. X. S. P.]. 



Comondu, L. Cal., Mex., \\\, 1889, (C. D. Haines), 4 cf, I juv. d", i juv. 9, 

 [Cal. Acad. Sci. and Hebard Cln.]. 



San Jose del Cabo, L. Cal., Mex., 13 d', 6 9 , type, allotype, paratypes, 6 juv. d^, 

 7 juv. 9 , [Hebard Cln., Cal. Acad. Sci. and A. X. S. P.]. 



Jojutla, Morelos, Mex., \'III, 4, 1903, (W. L. Tower), i a". [Tower Cln.]. 



Iguala, Guerrero, Mex.. IX, 1888, i cf , [Hebard Cln.]. 



Arenivaga erratica Rehn (Plate IX, figures 11 to 13.) 



1903. Homoeogamia {Arenivaga) erratica Rehn, Proc. Acad. Xat. Sci. Phila., 1903, 

 p. 187. [d^; Prescott, Arizona.] 



The present insect is closely related to A. apacha; males may be 

 separated by the distinctive dextro-ventral concealed genital 

 plate in that species, while in erratica the interocular width is 

 normally less than, very rarely equal to, that between the ocelli, 

 and the pronotal marking is normally less decided and never pic- 

 tured. Xo males of the present species before us have the teg- 

 mina much suffused with darker brown, a condition which occurs 

 frequently in apacha. Females of the two species are separable by 

 the decidedly hea\ier and shorter limbs in apacha, this most 

 noticeable in the tibiae; in apacha the fringe of hairs about the 

 cephalic margin of the body is also appreciably heavier. 



This species, with A . rehni and apacha, averages decidedly smaller 

 than A . hoUiana, but se\-eral males of the present insect from central 

 Texas are larger than the smallest males of boUiana before us. As 

 in the other species of the group, this size xariation appears to be 

 due rather to peculiar local environmental conditions, than to 

 purely geographic influences. 



In addition to the characters gi\en in the key, the following 

 features are of diagnostic value in the male sex. 



MEM. AM. ENT. SOC, 2. 



