March, 1914] Wheeler: Ants from Hidalgo, Mexico. 59 



of the head is also brown but of a lighter tint than the portion behind the eyes. 



^^'orke^ minor. — Length 5—5.5 mm. 



Differing from the worker major only in its somewhat smaller size and the 

 somewhat more elongate head, with less convex sides. 



Female. — Length 6.5 mm. 



Also very much like the worker major, but the head is distinctly longer 

 and narrower and the cheeks are nearly straight. Scutellum with a few erect 

 hairs. Wings very long (g mm.), slightly infuscated, with brown veins and 

 stigma. 



Described from eleven workers and a single female taken at 

 Guerrero Mill from a colony nesting in the trunk of a live oak. 

 I have described this form at length because of the meagreness of 

 Norton's original description of nifidiis (Proc. Essex Inst. 1868, p. 2) 

 which was based on three minor workers " from the mountains of 

 Orizaba ", where the species lives in " little companies under the bark 

 of pines" (Amer. Natur. II, 1868, p. 60). It was more fully char- 

 acterized by Forel (Bull. Soc. Vaud. Sc. Nat. XVI, 1879, p. 82). 

 The specimens from Hidalgo evidently represent a distinct variety as 

 their thorax is much paler than in the typical form, judging from 

 Norton's description. Comparing them with a few cotypes of 

 C. montivagus Forel taken by Stoll at Tecpam, Guatemala (7,000 ft.), 

 I find that the latter is scarcely more than a variety of nitidiis and not 

 a distinct species as Forel maintained in Biol. Centr. Amer. Formi- 

 cidas, 1 899-1900, p. 154. 



38. Camponotus andrei Forel var. cholericus new var. 



Worker major. — Length 6.5-7 mm. 



Head more elongate than in the worker major of the typical form and with 

 a deeper impression in the middle of the anterior border of the clypeus. Epi- 

 notum distinctly lower and more sloping. Hairs covering the body snow white 

 instead of yellowish. In other respects like the typical form of the species. 



Worker minor. — Length 4—4.5 mm. 



Closely resembling the corresponding phase of the typical andrei, but the 

 epinotum distinctly less angular in profile and more sloping, and the hairs on 

 the body more brilliantly white as in the worker major. 



Male. — Length 5 mm. 



Resembling the minor worker in sculpture and pilosity, but the body 

 entirely black, including the mandibles, antennal funiculi, tarsi and genitalia. 

 Wings whitish hyaline, with dilute yellow veins and brown stigma. 



Described from numerous workers and several males taken at 

 Pachuca in the ground under stones in arid territorv. The workers 



