84 
Psyche 
[September 
genus Lithomyrmex (later changed to Eulitho?nyrmex 3 ) from the 
Miocene Florissant Shale of Colorado. The condition of the shale 
fossils is of course much inferior to that of amber specimens, and 
Carpenter was unable to make out some important characters of 
Eulithomyrmex , including the shape and position of the compound 
eyes, presence or absence of antennal scrobes, status of tibial spurs, 
etc. The venation of the queen wing, the broad head, and the form 
of the petiole, postpetiole and downturned gaster were enough, how- 
ever, to make reasonable a placement of Eulithomyrmex in the same 
tribe as A groecomyrmex. The diagnosis of the tribe offered below 
is based mainly on A groecomyrmex and the new genus Tatuidris , but 
it is thought to agree with such characters of Eulithomyrmex as are 
known. 
Tribe Agroecomyrmecini (emended) 
Worker: Body short and compact, with hard, heavy integument, 
apparently capable of inrollment during lethisimulation. Head broad; 
eyes convex, set far back on the head, each at the posterior end of 
a well-marked, broad and deep antennal scrobe. Antennae robust, 
7- or 12-segmented, with large apical segment. Mandibles robust, 
triangular. Clypeus broad, with transverse free margin. No ocelli. 
Alitrunk short and broad, but not as broad as head, convex above, 
dorsal sutures obliterated; propodeal declivity bounded by carinae 
with or without short teeth above. Petiole sessile, short and thick, 
with a prominent process beneath. Postpetiole short, deep and very 
broad, with the sternite well-developed; broadly attached to the first 
gastric segment, which is large and strongly downcurved. Remain- 
ing (apical) segments of gaster forming a cone directed downward 
or even anteriad. Legs robust, with slender simple tarsal claws; 
middle and hind tibiae each with a pectinate apical spur. 
Female (not known for the new genus) : Like worker, but 
winged and with the other usual caste differences. Forewing vena- 
tion retaining all of Rsf2-3, though Mf2 is wholly contracted and 
lost. 
3 By a very unusual coincidence, Clark (1928) had preceded Carpenter 
by a few months in the use of the name Lithomyrmex for a living genus 
of Australian ants, now considered to be a synonym of Amblyopone. 
Clark’s paper, published in Western Australia, did not reach the United 
States for some time, but Carpenter (1935) eventually proposed Eulitho- 
myrmex as the necessary substitute for his fossil genus. 
