Tribe HETEROGYNA. 

 Family FORMICID.E. 



Subfamily DORYLIN^. 



The species contaiued in this subfamily are remarkable for the 

 great difference between the worker ( ^ ) and the male (6), and 

 also between the male (d ) and female ( $ ) so far as the last is 

 known. The S is a large wasp-like insect possessed of well- 

 developed large eyes and ocelli : the ^ of the two genera found 

 within our limits is blind, and in an American genus has no 

 facetted eyes but merely a single ocellus on each side of the 

 head. The $ is apterous and blind, with an immensely developed 

 massive abdomen a little resembling a $ termite. 



The ^ in the Indian species possesses a stiug ; the head may 

 be rectangular or oval ; the pedicel consists of one or two joints ; 

 the pupae are enclosed in a cocoon. 



Kei/ to the Genera. 



a. Pedicel one-jouited Dorylus, p. 1. 



d. Pedicel two-jointed .Enictus, p. 6. 



a. Of comparatively large size, length over 18 mm. ; 



node of pedicel convex , . . . Dorylus, p. 1. 



b. Smaller, length under 13 mm. ; node of pedicel 



concave, sometimes merely longitudinally grooved 



or bilobed, never convex ^Enictus, p. G. 



Genus DORYLUS. 



Dorylus, Fabr. Ent. Si/sf. ii (1793), p. 305, cJ . 



Type, D. helvolus J , Linn., from Africa. 



Range. Africa and Asia. 



The c? , $ , and ^ of this genus differ very considerably in 

 appearance, and were for a long time classed in different genera. 

 The cJ is a long, narrow-bodied, wasp-like insect, with very large 

 and prominent eyes and ocelli ; the mandibles are comparatively 

 long, more or less flattened and curved inwards ; the thorax is 

 gibbous and raised above the plane of the head ; posteriorly the 

 median segment has always a more or less steep slope to the apex ; 

 the femora are always compressed. The pedicel is one-jointed, 

 and either cup-shaped, rectangular, or square, invariably convex 

 above and carinate beneath. 



VOL. II. B 



