THE FEMALE OF ECITON SUMICHRASTI NORTON, 
WITH SOME NOTES ON THE HABITS OF 
‘TEXAN ECITONS.! 
WILLIAM MORTON WHEELER. 
One of the most interesting problems confronting the stu- 
dent of ant life in subtropical and tropical America is the 
determination of the sexual forms of the foraging, or driver, 
ants (Ecitonini), These ants are known only from a study of 
the workers, as the corresponding male and female forms, 
which are so aberrant as to have been placed in different 
genera, have not been satisfactorily determined in any one of 
the known species. The state of our knowledge of the sexes 
of the Dorylides (including the African species of Dorylini) up 
to 1899 is summarized by Sharp in the Cambridge Natural 
History? as follows: 
. The females of the Dorylides are amongst the rarest of insects and are 
also amongst the greatest of natural curiosities. Although worker and 
female ants are merely forms of one sex, — the female, — yet in this sub- 
family of ants they have become so totally different from one another in 
size, form, structure, and habits that it is difficult to persuade one’s self they 
can possibly issue from similar eggs. In the insect world there are but few 
cases in which males differ from females so greatly as the workers of Dory- 
lides do from the females, the phenomena finding their only parallel in the 
soldiers and females of termites ; the mode in which the difference is intro- 
duced into the life of the individuals of one sex is unknown. . 
The specimens of female Dorylides that have been jrid diy; after 
fifty or sixty years of research, be counted on the fingers. As the greatest 
confusion exists in entomological literature owing to the forms of a single 
species having been described as two or three genera, the following sum- 
mary of the principal names of genera of Dorylides may be useful : 
Eciton = the workers; Labidus = male; 9 unkno 
Pseudodichthadia ; female only known, possibly i of Eciton. 
Cheliomyrmex ; workers and soldiers only known. 
! Contributions Jrom the nega TA of the Jopu = e 
Director W. M. Wheeler, No. 2 Vol. vi, pp. 179, I 
563 
