HYMENOPTERA PETIOLATA. 773 



onies seem small. P oner a contracta and P. punctatissima are the sole 

 British representatives. The latter is peculiar in that it has two 

 kinds of male, one winged and one wingless. Myrmecia, the bull-dog 

 ant of Australia, forms great mounds of earth. 



Sub-fam. 5. Dorylinae. Clypeus minute and antennae arising close 

 to front edge of head ; abdomen drawn out, more or less cylindrical ; 

 pedicel imperfect, occasionally consisting of two nodes in the workers ; 

 the several castes very different ; the females and workers often 

 wholly blind, or at any rate without facetted eyes. This sub-family 

 includes certain wandering ants which retain their social distinctions 

 though they have no permanent home. Eciton (Fig. 504) is a well-known 

 American genus which makes temporary shelters in hollows in trees, 

 the members of the community massing together like a swarm of 

 bees. But they have no abiding resting-place, and often leave 

 their shelter on marauding expeditions and do not return. The 

 genus formerly known as Ldbidus is now regarded as the male Eciton. 

 Dorylus closely resembles this last-named form ; but the female, 

 formerly classed in a separate genus, in some forms is enormously 

 enlarged, somewhat as in the Termites ; the workers are blind but 

 predaceous, and the communities rove. 



Sub-fam. 6. Amblyoponinae. No true pedicel ; the articulation 

 between the second and third abdominal segments is broad. 

 This group has relations with the Scoliidae as well as with 

 the Formicidae. Amblyopone and Stigmatomma are thought to be 

 subterranean and social, but little is known of their habits. Both 

 sexes are winged and the workers are nearly blind. 



