No. 411.] MALES OF SOME TEXAN ECITONS. 173 
Pergande. Through this kindness Rev. Mr. Schmitt has enabled 
us to complete our description of the sexual forms of Æ. opaci- 
thorax, the male of which is described above. Comparison of 
the female of this species with the female of Æ. schmitti 
shows such striking similarity that unless the specimens had 
been taken with workers of two very different species, one 
would scarcely regard them as specifically distinct. The fol- 
lowing slight differences can be noticed: The female Æ. ofaci- 
thorax has the head somewhat more shining, with smaller 
punctures, which are not confluent as in Æ. schmitti; the 
eyes are smaller, the hairs on the dorso-lateral portions of the 
head are shorter, the occiput is distinctly less depressed in 
the middle line, and 
the pronotum is some- : fs: 
what rounder and more gs >W 
N » » 
«33 s> 
convex above. The 
thorax is less conflu- 
ently punctate, more 
evenly hairy, and the 
petiole is less concave 
in the middle. The 
size and color of the 
two species are very 
nearly identical; even 
the large dark blotches 
on either side of the 
metanotum are present 
in Æ. opactthorax. 
If we may be per- 
mitted to generalize from the study of the two species of 
Eciton, of which we have seen all three phases, it may be 
said that the fertile forms of the different species of this genus 
are even more difficult to distinguish from one another than 
the workers. For this reason, and also on account of the much 
greater rarity of the males and females, myrmecologists will 
probably continue to regard the worker ecitons as of greater 
taxonomic importance. 
UNIVERSITY OF TEXAS, AUSTIN, TEXAS, Nov. 15, 1900. 
Fic. 3:— Eciton opacithorax Emery. 
