THE DRIl'ER AND LEGIONARY ANTS. 255 



Wroughton has seen the workers of the Indian IE. wroughtoni 

 expelling the males from the nest. These males escaped on two 

 consecutive days from " a small hole in the floor of a mudwashed 

 verandah, and it did not appear to be a hole used for the regular traffic 

 of the nest." It is an interesting fact that the males of the Dorylii 

 have nearly always been found escaping from holes in the floor or 

 foundations of human dwellings. 



In tropical and subtropical America the Dorylinae are represented 

 by two genera, Eciton and Cheliomyrmcx. Of the former about sev- 

 enty species are known, of the latter but one, C. nortoni. The genus 

 Eciton is so homogeneous that it has been split into only two subgenera, 

 Acamatus and Eciton s. str. It resembles the Old World JEnictus in 

 having the pedicel two-jointed in the worker, and in the structure and 

 smaller size of the female. Both worker and female usually have 

 vestiges of eyes, consisting of a single ommatidium on each side of the 

 head, but not connected with the brain by means of optic nerves, so 

 that they must be useless as visual organs. In some species (E. hania- 

 iiim (Fig. $C and 145), lucanoides and forcli) the largest workers, or 

 soldiers, have peculiarly elongated and hooked jaws of unknown func- 

 tion. The males of Eciton resemble those of Dorylns ( Figs. 146 and 

 I47af), but they are smaller, have two complete cubital cells in the 

 wings, and their mandibles are usually longer and more falcate. 



As in the case of Dorylus, the three phases of Eciton have been 

 placed in as many different genera, the worker in Ec'ton, the female in 

 Pseudodichthadia and the male in Labidus. Hetchko, Mayr (i886b) 

 and W. Miiller (1886) first showed that the insects which entomologists 

 had been in the habit of calling Labidus were the males of Eciton, and 

 Ern. Andre has recently found that the insect which he described as 

 Pseudodichthadia inccrta is the female of E. ccccnm. Although the males 

 of several species are known, few have been taken with their workers, 

 and are described in the literature under independent names. In addi- 

 tion to that of E. caecum the females of only three species' are known, 

 that of E. opacithorax, discovered by Schmitt in North Carolina, that 

 of E. carolinense taken by Forel in the same state, and that of E. 

 schmitti (Fig. 147*:) taken by myself in Texas. All the phases are 

 known only of E. caecum, opacithora.r and schmitti. 



The genus Chelionivnne.r is confined to the warmest parts of America 

 and appears to be rare except in certain localities. I have recently 

 received a number of specimens of C. nortoni (Fig. 148) from British 

 Honduras, but it is recorded also from Colombia and Mexico. Only 

 the worker form is known, and that is remarkable for the hooked and 

 bidentate mandibles of the soldier form, and in having only a single 



