Article beginning on page 387.
Psyche 9:387-392, 1900.

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PSYCHE.
NEW AGRICULTURAL ANTS FROM TEXAS,*
WILLIAM MORTON WHEELER, AUSTIN, TEX.
Worker. Length 5.5-6.5 mm.
~ead rectangular, exclusive of the 7-tooth- ed mandibles slightly broader than long ; posterior margin slightly concave. An-
terior border of clypeus broadly but faintly excised. Frontal area triangular, as broad as long, with a distant median carinula. Eyes in the middle of the lateral surfaces of the head. Antcnnal scape reaching to midway
between the eye and the posterior corner of the head. Thorax of the usual shape, with two rather slender epinotal spines about a6 long as their distance apart at the base, di- rected obliquely upward, backwards and out- wards. Petiole compressed at the base, its peduncle shorter than its node, which is pointed in front so that the ascending dorsal surface forms an obtuse angle in profile; posterior descending dorsal surface gently convex ; lower surface of petiole with a very distinct downwardly directed tooth. IJost- pctiole campanulate, slightly broader than Iong, its ventral protruberanee very small but distinct. Gaster and leg's of the usual con- figuration.
Mandibles with coarse, parallel striae.
Frontal area smooth and shining.
Clypeus,
sides and upper surface of head traversed by ĺ´ver delicate parallel rugae, which are very close together and scarcely divergent pos- teriorly. Interrugal punctures indistinct and in a single row between each pair of Wontributions from the Zoological Laboratory of the University of Texas, No. 34.
rugae.
Posterior angles of head smooth mid
shining.
Thoracic and coxal rngae mostly
transverse, even 011 the nieso- and metapleu- rae. Infraspinal facet of epinolu~r~ smooth and shining. Petiole, postpetiole and legs covered only with delicate micro'icopic retic- illation.
Trunk and legs 'beset with bristly pale
yellow hairs which are erect on the dorsal surface of the head and thorax and suberect on other portions of the body and append- ages; the erect hairs on the head are only about half as long as those on the thorax. Lower surface of head and mandibles with the usual beard of long recurved hairs. Pu- bescence none.
Whole ant yellowish red with the es-
ception of the eyes and dentate mandibular edges, which sire black.
This specieswas taken (Dec. 19,1901)
in several localities in Presidio County, Trans-Pecos Texas, from the southern
end of Fresno Canon northward through
Alamito to San Esteban, which is located a few miles south of Marfa. These
localities have an elevation of 4000-5000 ft. The species occurs also in New
Mexico, whence I have received a worker
taken by Prof. T. I). A. Cockerel1 at
Mesilla Park ("in the Pluchea zone.")
At first sight P. descrforum resembles
P. califor-nims Eucklcy on account of
its yellowish red color. It differs, how-



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888 PSYCHE [September, 1902
ever; from this species in possessing
epinotal spines and smooth posterior
corners to the head and from this and
all other described North American
species in the very dense and delicate
cephalic rugae.
P. herforum inhabits the dry stony
soil above the floodmarks of the streams on the cailon sides where there are only a few xerophytic shrubs like Fozpiwa
me.xicana, Lawea mexica~za, and .Flour-
ensia cemna. In the open sun-lit spaces
among these shrubs the ants make soli-
tary mounds 4-6 inches across and per-
forated in the centre with an entrance
about 4 inch in diameter. They
feed on the seeds of a coarse, tufted
grass (Munroa sp.) which is found
growing- sparsely near the nests. After
the diminutive seeds are removed from
the relatively voluminous chaff, the latter is deposited by the ants on the mound
immediately around the entrance of the
nest. Occasionally the new species
builds its nests under single or clustered stones like 7, imiierbicuhts Wheeler.*
None of the nests contained more than a
dozen workers, but the weather was very
cold and dry and the bulk of the colony
may have been hibernating at some in-
accessible depth in the stony soil. There can be no doubt, however, that the colo- nies of this species are very much smaller than those of P. tarhatiis and P. occi-
denialis.
Worker. Length 7.5-9. mm.
Head rectangular, exclusive of the 7-
toothed mandibles as broad as long ; posterior margin straight. Anteriorborder of clypeus with a dccp, broad, almost sen~icircular ex- cision. , Frontal area triangular, distinctly longer than broad, convex but scarcely car- nulate in the middle. Eye in the middle of the lateral surface of the head. Tip of an- teonal scape reaching to midway between the eye and the posterior angle of the head. Thorax shaped like that of P. harbalus but without epinotal spines, their position being indicated in some specimens by a pair of rather short indistinct ridges or projections. Petiole short, the node longer than the
peduncle and much lower and blunterthan in Ixirbtttus, the anterior ascending and posterior descending dorsal surfaces of about equal length, the former slightly concave in profile hut not distinctly angular as in barbatas, the latter depressed in front and slightly concave behind. Tooth on the ventral surface of
petiole obsolescent. Postpetiole campan- date, slightly longer than broad, evenly con- vex above, its ventral protuberance very slightly developed as compared with bar- bafus. Gaster and legs of the usual ap-
pearance.
Mandibles shining, coarsely and deeply
striated. Frontal area opaque. Front and sides of head covered with numerous, paral- lel, clean-cut rugae and with small piliger- ous punctures. The rugae are somewhat finer than those of barbatus and scarcely diverging except on the extreme posterior portion of the head. Interrugal sculpture indistinct, consisting of very shallow, confluent foveo- lac. On the posterior angles the rugae are replaced by a delicate reticulation and this disappears to leave the corners of the head smooth and shining. Thoracic sculpture
like that of the typical barbatus but some- what finer, the prevailing directions of the rugae being transverse on the pro- and
epinotnm and longitudinal on the mesonotum



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September, 19021 PSYCHE. 389
and meso- and metapleurae.
Petiole, post-
petiole and gaster shining, covered with delicate, even, microscopic reticulation. Upper surface of petiolar node with a few faint longitudinal rugae. Coxae faintly
rugose and, like the remainder of the legs, covered with delicate microscopic reticula- tion.
Body and appendages beset with bristly,
pale yellow hairs, very longand projecting forward on the clypeus, shorter and erect on the upper surface of the head and thorax, suberect on the remainder of the body.
Beard of long, recurved hairs on the lower . surface of the head and mandibles well devel- oped. Pubescence none.
Whole ant deep ferruginous red, excepting the following- portions which are black: dentate edges of mandibles, anterior border of clypcus, eyes, ventral edges of the pleurae and sutures between the petiole and post- petiole and between the latter and the gaster. Described from numerous specimens
collected in the open spaces among the
dry chapparal and mesquite thickets
near San Pedro Springs, San Antonio,
Texas, on the anniversary of the battle
of San Jacinto (April 21, 1902).
P. sancti-hyacinthi superficially re-
sembles p. barbatus var. mokfaciem
Buckley but besides its somewhat smaller size the new species may be very readily distinguished by its very deeply excised clypeus, the straight occipital border,
the smooth and shining posterior angles
of the head,* the absence of the epinotal spines, the smooth petiole and post-
petiole, the much more depressed and
rounded petiolar node and obsolescent
*The last character is sometimes, though rarely, found in barbafw.
ventral tooth, and the conspicuously
smaller ventral protuberance of the post- petiole. It differs from P. califommi-s
in its larger size, deeper coloring, the extent of the clypeal excision, sinootl~ posterior angles of the head and blunter petiolar node.
Although it is very easy at first sight
to confound P. sancfi-hyacintJii with P. mole~aciens, which occurs in the same
locality, this is not the case with the
nests of the two species. Instead of
huge gravel cones or extensive discs, the former species builds only small, flat,
dirt-cones, sometimes in close clusters of two, three or four, and each measuring
not more than 4-8 inches across, with a
central perforation about & inch in diam- eter. The periphery of each mound is
often covered with a thick layer of chaff and other vegetable debris which has
been cast away by the ants and may be-
come the abode of colonies of termites.
The nests are much less populous than
those of P. molefacie?zs.
POGONOMYRMEX BARBATUS F. Smith
Var. NIGRESCENS, Var. nOV.
The worker of this striking variety
differs from the typical barbatus of
Mexico in its smaller size and the deep
reddish black coloration, not only of the head and thorax as in the Mexican form,
but also of the antenna1 scape, petiole, postpeliole, gaster and femora. The
tip of the easier is very nearly as dark as the base. Mandibles, funiculus, tibiae, tarsi and peduncle of petiole deep fcr-
ruginous red. Sculpture like that of the



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390 PSYCHE. [September, 192
typical lia?+ati;s, the rugae being often very coarse and irregular on the prono-
turn. Coarse hair covering the body
grayish white ; beard rather scanty and
almost absent in several of the speci-
mens.
Described from 14 workers kindly
given me by Mr. A. M. Ferguson, They
were collected at Eagle Pass, Tex. by
a lady who found them carrying away
the buds of the singular gnetaceous
Ephedra d-nfisyphilitica. Two other
specimens which evidently represent a
transition to P. tarbatus var. marfensis Wheeler were collected at Mesa Negra,
San Ildefonso, New Mexico by Mr. E. L.
Hewitt and Miss Ruth Reynolds. In
these specimens the petiole and post-
petiole are red, the former being dis-
tinctly grooved longitudinally. The
beard is well developed.
The addition of the preceding variety
and two species to our fauna leads me
to revise my recently published table of the North American Pogoizomyrmex.*
A third species, 2'. schmitfi from Hayti has also been recently described by
Forel.? As this West Indian species,
the Texan imterbimlus Wheeler and the
Brazilian nigelii Fore1 form a compact
group of forms more closely related to
one another (in size, sculpture, absence of beard, etc.) than to any other species of the genus, they may be included
in a distinct subgenus for which I
would propose the name ~fhebomj~rmex.
Pogmo~nj~rmex sensu lato would then
comprise the species of the genus prop-
er, the subgenus Janetia Forel (with the single species J. myri Fore1 from
Colombia) and the subgenus here pro-
posed. The workers of the nine known
North American species of Pogonomj~rmex
may be distributed as follows :
*Small species, less than ;; mm. long;
under surface of head witliout a beard of long recurved hairs ; epinotum with four spines ; head, thorax and petiole reticu- late-rugose. (Ephelmmyrmex, subgen.
nov.)
I. Color red - iml)erbiculus
Wheeler.
2. Color black- schvzitti Forel.
*Large species, more than 5 mm. long ;
under surface of head with beard of long recurved hairs; epinotum unarmed or with only two spines; head and thorax fine-
ly rugose, the rugae parallel and not dis- tinctly reticulate. (Pogonoinyrmex s. str.) + Epinotum with a pair of spines.
Posterior angles of head smooth
and shining. Sculpture of head
and thorax very fine. desertorurn,
sp. nov.
$9 Posterior angles of head not
smooth and shining. Sculpture
coarser.
A. Head evenly and finely
rugose, rugae but little divergent
posteriorly, without distinct inter-
rugal sculpture. barbatus Smith.
I. Head, thorax and legs
black ; petiole, postpetiole
and gaster red.
liariiatm Sm (typical).




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September, r002] PSYCHE. 391
2. Cephalic rngae finer and
denser, body ferruginous
throughout.
var. nzulefaczeas Buckley.
3. Head and thorax brown-
ish red, gaster in part or
entirely brown, rugosity as in
No. 2 or somewhat coarser.
var. fuscatus Emery.
4. Kugosity a little coarser
than in No. I ; head, thorax
and legs black, petiole and
postpctiole brown, abdomen
red, node of petiole longitu-
dinally rugose.
var. marfensir Wheeler.
5. Color reddish black, ped-
uncle of petiole, tibiae, tarsi
and funic~~lus red ; sculpture
a in no. I. ; beard scanty.
var. wsceq var. nov.
0. Head and thorax much
more coarsely rugose than in
Nos. 1-4. Rngae irregular
in direction on the pro-
and mesonoturn, transversc
elsewhere on the thorax.
Petiole rather coarsely and
irregularly rugose; its ped-
uncle shorter than in No. I ;
poslpetiole rugose-punctate.
subsp. rz~~ostis Emery.
B. Head less densely rugosc;
the rugae distinctly divergent
posteriorly ; interrugal spaces
densely and distinctly foveolale-
punctate.
a. Ventral surface of petiole
without a distinct tooth ; in-
fraspinal facet of epinotum
rugose, scarcely shining.
occidenialis Cresson.
I. Head opaque, interrugal
punctures very distinct.
occidrntalis Cr. (typical).
2. Head more shining, in-
terrugal punctures less pro-
nounced ; petiole less opaque
than in No. I.
var. su/;nitidtis Emery.
b. Petiole with a distinct tooth
below; infraspinal facet of
epinotum shining, without
rugae. s'/i/;dmtatus May.
t Epinotum without spines.
S Posterior angles of head smooth
and shining; clypeus deeply ex-
cised. sancfi-hya.cinf.hi, sp. nov.
5 Posterior angles of head not
smooth and shining ; clypeus not
deeply excised.
a. Interrugal spaces of head
indistinctly and confluently
punctate ; workers mono-
morphic. ca/ifor?zicus Buckley.
I. Color yellowish red,
peduncle of petiole about
the same length as the node ;
postpetiole as high as long.
cahfornicus Buckley (typical).
2. Darker red: apical third
or more of gaster black;
petiole and postpetiole often
brown, the tormer slender,
its node longer and less
erect with rounder or but
slightly pointed apex.
var. i:s/dmiius Pergande.




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PSYCHE. [September, igoz
3. Yellowish red, gaster
brown except at the base ;
peduncle shorter than the
very long node, which is
pointed above ; postpetiole
not as high as long. Sculp-
ture fainter than in No. I,
petiole and postpetiole punc-
tate, without rugae.
subsp. longinadis Emery.
I]. Interrugal spaces of head
regularly foveolate-punctate.
Color ferruginous red. Work-
crs polymorphic, i. e. with size
of head greatly varying.
badws Latr.
AUSTIN, TEXAS, May 10, 1902.
POSTSCRIPT.
As the result of recent collecting trips in Central and Trans-Pecos, Texas, I
am able to add the following brief notes on some of the species of Pogonomyrmex
of the above table and on a new species
and subspecies which came to light too
late to be included.
I. Pogonomyrmex - @ache, sp. nov.
This is a fine orange-yellow species,
nearly as large as barbatus, with smooth posterior angles to the head and without epinotal spines. It is decidedly larger
and more robust than californicfu, which it resembles in sculpturing, and the
cone of the petiole is blunter and more
depressed. It differs from sa?zcti-hyacin- thi in coloration and in having a less
deeply excised clypeus. Only four
isolated nests of apache were seen.
These were excavated in the dry, stony,
adobe soil about Fort Davis in Jeff Davis County. They were in the form of
small chaff-strewn mounds, 3-5 inches
across, perforated with an entrance
about 4 inch in diameter, and containing hardly more than 25-50 workers. Near-
ly all the workers were busily engaged
carrying home grass-seeds. When run-
ning they carried the abdomen in a
peculiar elevated position.
2. P. accidentalis subsp. commche,
subsp. nov. This form differs from the
typical occidentalis and resembles subniti- h s Emery in the less opaque surface
of the head and thorax. It is mainly
distinguished, however, by the very short epinotal spines, which are hardly half as long as those of the typical form. It
was discovered near Milano, Millan
County, in the sandy soil of the open
post-oak woods. Here it constructs
small mound-nests not more than 4-6
inches across and very unlike the great
gravcl cones constructed by the typical
form in Wyoming and Colorado. There
wcre not more than 50 ants in a nest.
At Langtry, in Valverde County, small
colonies of the typical occidentalis wcre seen inhabiting similar nests on a sandy spot in the Canon of the Rio Grande.
3. P. sancti-hyacinthi. This species
is common at Fort Davis, where it builds small obscure nests among the disinte-
grating volcanic rocks on the summit of
the " Crouching Lion " (altitude about
5400 ft.). While running this species
does not carry the abdomen conspicu-