AMERICAN MUSEUM NOVITATES Published by Number 1079 THE AMERICAN MUSEum OF NATURAL HISTORY July 17, 1940 New York City

A REVISION OF THE FORMS OF STIGMATOMMA PALLIPES BY WM. S. CREIGHTON Although the habits of Stigmatomma the North American representatives. The pallipes have been repeatedly studied range of oregonensis is strictly limited to none of these publications have been of the coastal region of the Pacific Northwest. much service to those who wish to deal Its nearest neighbor from a spatial stand- with the taxonomy of this interesting point appears to be the form described in species. This paper is an attempt to bring this paper as subterranea, which occurs in together and evaluate the scattered taxo- central Kansas. The Kansas variant is nomic publications which deal with S. scarcely less isolated from the eastern pallipes and its variants. Although ref- pallipes whose range does not seem to erences to this insect have repeatedly extend west of Michigan. As I shall show appeared in articles of a descriptive char- in a subsequent paragraph there is some acter there seems to be no adequate de- reason to believe that the ranges of the scription of the typical form. The ease variants are not as widely separated as our with which this insect may be recognized present scattered locality data would and the fact that it is our only species have indicate. Yet it is true that to the present fostered the notion that a thorough de- there are only two forms whose ranges are scription is not necessary. At one time adjacent. The range of the typical pallipes this may have been true, but the subse- borders upon that of the form herein de- quent recognition of several geographical scribed as montigena. Where these two races has made it imperative that the forms come in contact is produced the characteristics of the typical form be more intergrade which Santschi has called the clearly defined. variety wheeleri. Because of this con- The status of the several North American sideration I have treated all the forms of variants of Stigmatomma is by no means S. pallipes as subspecies because I believe easy to determine. Unlike most other that they are geographical races. Ac- ponerines which occur in this country cording to my view the status of this com- Stigmatomma does not increase in abun- plex is as follows: dance as one goes southward. It is difficult 1.-S. pallipes Haldeman (1844) to find in the Gulf States, where other = subsp. arizonensis Wheeler (1915) var. wheeleri Santschi (1913) = hybrid ponerines occur in abundance. It appears pallipes X montigena to be absent in southern Florida and the 2.-Subsp. montigena, new subsp. Brownsville area in Texas. There are no 3.-Subsp. oregonensi8 Wheeler (1915) representatives known from Mexico or 4.-Subsp. subterranea, new subsp. Central America and only a single species, Before passing to the descriptions I wish the Cuban bierigi, from the West Indies. to comment on a peculiarity of the sub- Other New World species of Stigmatomma species subterranea which may lead to an occur in southern Brazil, northern Argen- alteration of our views concerning the tina and northern Chile. The situation is, ecology and distribution of this group of therefore, quite unlike that characteristic forms. It has been generally assumed of most of our ponerines which are properly that pallipes and its variants are limited regarded as northern fringes of Neotropical in their distribution to areas which are groups. This discontinuous distribution, characterized by considerable precipita- which is characteristic of the genus as a tion and heavy cover. The importance of whole, is scarcely less striking in the case of cover has been stressed by Haskins (Jour. 2 AMERICAN MUSEUM NOVITATES [No. 1079

N. Y. Ent. Soc., XXXVI, pp. 179-184, erence for moist, wooded regions. In 1928) who holds that pallipes has lost the preparing this paper I had for study a ability to utilize open fields or glades as series of workers taken by me at Elmo, nesting sites. While this latter view is Kansas, in the summer of 1927. These probably too extreme, it is unquestionably insects, described in the present paper as true that most of the published locality the subspecies subterranea, were living in data for pallipes indicates a strong pref- a small crevice between limestone frag- ments fully three feet below the surface of the ground. The nest was discovered by accident and, since it was laid open with a pick, all passages leading to the surface (provided there were any) had been obliterated before the ants were exposed. As to whether such passages existed is a matter of secondary importance. The significant fact is the presence of a nest of Stigmatomma at the edge of the Kansas 7 prairies. The country in the vicinity of Elmo is a rolling, open area where the only trees are borders of osage orange along the edges of the fields. Cover there is none, as will be fully appreciated by anyone who has worked there under an August sun. Elmo is one of the last places where one would expect to find Stigmatomma if its distribution is dependent on moisture and cover. The conclusion seems inescapable that Stigmatomma can tolerate a much wider range of ecological conditions than 4- has been hitherto supposed. In all prob- ability its range includes much of the United States, but it is only in those por- 8 tions of the range where abundance of cover and moisture prevail that the insect becomes epigaeic and, hence, liable to .5 discovery by collectors.

KEY TO THE WORKERS OF THE SUBSPECIES OF S. pallipes 1.-The portion of the inner border of the mandible which bears the double teeth 6 notably convex (Fig. 1) ...... 2. The portion of the inner border of the Fig. 1. Mandible of S. !pallipes pallipes. mandible which bears the double 2. teeth Fig. Mandible of'S. pallipes oregonensis. straight or nearly so (Fig. 2) (Coastal area Fig. 3. Edge of clypeus of S. pallipes oreg'or- in the Pacific ernsis. northwest) ...... pallipesoregonensis. Fig. 4. Edge of clypeus of S. pallipes sub- 2.-Funicular joints 2-5 almost twice as broad terranea. as long; (Fig. 8); clypeus usually strongly Fig. 5. Edge of clypeus of S. pallipes palli'pes. projecting; largest workers 5 mm. in Fig. 6. Edge of clypeus of S. pallipe8 monti- -length (mountains of North Carolina at gena. elevations of 3000 ft. or Fig. 7. Antennal funicul'us Of S .pale more)...... pa....l.l.i.p.e.s..m.on....tig.en..a... pallipes. Funicular joints 2-5 at most very little Fig. 8. Antennal funicul'us- "f' S. pallipei broader than long and usually longer thari montigena. broad (Fig. 7); clypeus moderately pro- REVISION OF STIGMATOMMA PALLIPES

jecting or nearly straight; largest workers occurs between the outermost pair of teeth 6.5 mm. in length ...... 3. 3.-Occiput slightly but distinctly concave; and the powerful terminal tooth. Frontal median teeth of the clypeus smaller and lobes large and prominent, only slightly finer than the flanking tubercles (Fig. 4); divergent behind and enclosing between (central Kansas) .... pallipes subterranea. them a subeircular frontal area. Antennal Occiput flat; the median teeth of the clypeus almost as large as the flanking scapes stout, their tips in repose surpassing tubercles (Fig. 5); (eastern Canada to the a point midway between the antennal Gulf Coast and west to the latitude of insertion and the occipital angle by an Michigan)...... pallipes pallipes. amount equal to the greatest thickness of The foregoing key does not contain the the scape. Funicular joints 2-5 longer forms arizonensis and wheeleri because, as than broad in the large workers; in the noted above, the first of these is a synonym smaller workers these joints may be of the typical pallipes and the second an slightly broader than long. Funicular intergrade between pallipes and the sub- joints 6-10 gradually increasing in width; species montigena. the terminal joint about as long as the two preceding joints taken together. Eyes Stigmatomma pallipes Haldeman small, usually consisting of eight or ten S. pallipes, HALDEMAN, 1844, Proc. Acad. poorly defined facets but in some speci- Nat. Sci. Phila., II, p. 54 (Typhlopone) U.- EMERY, 1895, Zool. Jahrb. Syst., VIII, p. 261, mens there may be as many as twenty U 9 c .-WHEIELER, 1900, Biol. Bull., II, p. 65, facets. Figs. 5, 6, 7, Q 9 d. Thorax seen from above with a strong S. pallipes subsp. arizonensis, WHEELER, 1915, constriction in the region of the mesonotum Bull. Amer. Mus. Nat. Hist., XXXIV, p. 389, U . and the anterior portion of the epinotum. S. serratum, ROGER, 1895, Berl. Ent. Zeitschr., III, p. 251, U . Pronotum oval in outline except for the Atropas binodus, PROVANCHER, 1881, Cana- concave posterior face at the promesonotal dian Nat., XII, p. 207, U. suture. Mesonotum short and strap-like, S. pallipes var. wheeleri, SANTSCHI, 1913, its anterior face usually less curved than Ann. Soc. Ent. Belg., LVII, p. 429, U 9 e the adjacent face of the pronotum but in pallipes X montigena. some specimens the mesonotum may be WORKER.-Length, 4.5 mm.-6.5 mm. bowed forward giving it a roughly chevron- Head, exclusive of the mandibles, sub- shaped appearance. Epinotum subtrape- quadrate and as long as broad. Sides zoidal, the sides sloping outward from the very slightly narrowed at the insertion of impressed mesoepinotal suture to the flat the mandibles, more strongly narrowed declivous face. Thorax seen in profile toward the occipital angles, the latter with only the anterior half of the pronotum well marked. The occiput appears flat convex. The posterior half of the prono- in full-face view. Anterior edge of the tum is virtually flat and the mesonotum clypeus very slightly convex or straight, and basal face of the epinotum are quite the six or seven median teeth stout and flat. The mesonotum is usually slightly conical and only a little smaller-than the elevated above the remainder of the flanking tubercles. When the latter are thoracic dorsum. Basal face of the epino- completely divided the clypeus appears tum considerably longer than the de- to be armed with nine or ten teeth of clivous face which it meets at a sharp approximately equal size. Mandibles angle. Node of the petiole seen from elongate, linear; their border sinuate and above subcircular and slightly wider than with the convex central portion armed long in the large workers, more narrow and with four or five pairs of teeth. In the a little longer than broad in the smaller event that there are only four pairs of ones with the posterior border truncate. teeth it is always the outermost pair which Node of the petiole seen in profile with a is replaced by a single tooth. In addition short peduncle which passes immediately to the paired teeth each mandible is armed to the steeply sloping anterior face; the at the base by a single, large, triangular dorsal and posterior faces forming a single, tooth. A small single, subapical tooth feebly convex surface which meets the 4 AMERICAN MUSEUM NOVITATES [No. 107

anterior face at a sharp angle. Ventral this size difference is by no means constant. surface of the petiole with a large rounded The female and worker of pallipes are lamella projecting forward and down- identical as regards the structure of the ward. Constriction between the first and clypeus and mandibles. In the female the second abdominal segments well marked. tip of the antennal scape in repose just Sting long and powerful. fails to reach the level of the lateral ocelli. Sculpture: Mandibles and clypeus longi- The eyes of the female, which consist of tudinally striate and feebly shining; the about one hundred facets, are so situated antennal scapes, the entire upper surface that their anterior margin lies at the of the head and the sides of the pronotum middle of the side of the head (mandibles bearing punctures set so close together excluded). In sculpture and pilosity the that the surface appears coriaceous and female is identical with the worker. Wings dull in most lights. Genae and gula, the hyaline, the veins yellow, the dorsum of the entire thorax and the top of brown. pterostigma the node of the petiole with less numerous To date I have seen only six males of punctures and, hence, more shining. On pallipes and since these insects show con- the lower parts of the meso- and meta- siderable variations in details of sculpture, plurae the punctures are replaced by longi- pilosity and color I am unable to tudinal striae. The decide declivous face of the which of them ought to be regarded as epinotum is usually dull and covered by typical. Since the purpose of the above fine transverse striae but in some specimens description is to establish more these are so feeble that they do not dull the characteristics of certainly the shining surface. the typical pallipes Sides of the node of I prefer to make no attempt at this time the petiole and the entire first and second to describe the male. In all probability gastric segments with small and scattered the males of all the subspecies will be punctures and strongly shining. The found to be similar. remaining gastric closely segments strongly shin- The exact whereabouts of the type of ing and finely shagreened but punctured is unknown only at the pallipes if, indeed, it is still margins where erect hairs in existence. As Haldeman failed to give occur. any type in his Erect hairs fine, abundant and locality original description short it seemed difficult or impossible to secure except on the posterior gastric segments a where precise concept of the typical form. the hairs are longer and coarser. Because of these considerations it appeared Many of the hairs are subappressed and necessary to grade into pubescence on rely upon the consensus of the head, thorax, opinion which has chosen the large eastern petiole and anterior gastric segments. variant as Antennal the typical form. The above scapes, funiculi, tarsal joints was drawn and tibiae densely covered description from such speci- with short, mens. Since it was prepared, however, I erect hairs. Femora with fewer hairs than have had the of the rest of the legs. Mandibles with rela- pleasure examining two tively few hairs but autotypes sent by Haldeman to Harris. those much longer These valuable specimens are in the collec- and stouter than the other cephalic hairs. tion of the The clypeus usually bears Boston Society of Natural two or three History. I wish to express my gratitude very long erect hairs. The border of each to Dr. Richard of the posterior gastric Dow who brought the segments bears specimens to my attention and through numerous long, erect hairs which are whose I have notably stouter than those elsewhere with courtesy been enabled to the examine them. They prove to be identical exception of the mandibular hairs. with the eastern form Female: Except for its much bulkier meso- large which has been generally, and correctly, regarded as thorax, its notably larger eyes and the typical. presence of ocelli the female of pallipes is very In the following list of localities for the sinilar to the worker. It is usually have slightly larger than the worker (7 mm.) but typical pallipes been included those f Santschi's variety wheeleri. It may be 1940] REVISION OF STIGMATOMMA PALLIPES 5 admitted that it is not impossible to dis- with more nearly parallel sides and feebly cover fairly homogeneous nest series which developed teeth above the insertion of the show the characteristics of this form but mandibles. The first three criteria are, more often than not its recognition involves therefore, of little significance. The fourth the splitting of nest series. and fifth differences concerning sculpture Quebec: St. Joseph du Lac (G. Chagnon) and pilosity are negated by structure of Ontario: North Bass Island (M. Talbot) the type. The punctuation is no finer New Hampshire: Pelham (Bridwell) than that of the typical pallipes and the Massachusetts: Blue Hills, Ellisville (W. M. dorsum of the thorax is not opaque but Wheeler); Forest Hills (L. H. Taylor); Holliston (N. Banks); shining. There is abundant pubescence on Middlesex Fells (no collector); the upper surface of the head of arizonensis. Reading, Harvard (R. P. Dow); Finally a color distinction based upon a Naushon Island (W. M. single specimen is of questionable value Wheeler, W. S. Creighton) Connecticut: Colebrook (W. M. Wheeler) at best and, moreover, the immature speci- New York: Bronxville, White Plains (W. M. mens of the typical form have the ferru- Wheeler); West Farms (J. Angus); ginous color noted for arizonensis. As far Van Courtland Park, Tuxedo (W. as the writer has been able to determine S. Creighton); Lowville (H. Not- man); Valhalla (F. M. Schott) the only thing which distinguishes arizo- New Jersey: Garrett Rock (no collector); Short nensis from the typical patlipes is the Hills, Lakehurst (W. M. Wheeler) locality in which it was supposedly found. Virginia: Pennington Gap (H. G. Hubbard); That our common eastern form should Falls Church (N. Banks); Suffolk, Massaponax (W. S. Creighton) appear in the Huachuca Mountains of North Carolina: Durham (A. S. Pearce); Black Arizona is a matter worthy of carefu] Mountain (no collector) consideration. According to the locality Tennessee: Camden (F. M. Gaige) label the type of arizonensis was secured Alabama: Mobile, Spring Hill, Chicasaw (W. S. Creighton) by Dr. W. M. Mann in Ramsey Canyon Ohio: Jackson County (L. G. Wesson) at an elevation of 5800 feet. At the 5800 Illinois: Rockford (W. M. Wheeler); New foot level the zonal character of Ramsey Lenox (M. Talbot) Canyon is a rather peculiar one, repre- Michigan: Baraga County (no collector) senting, as far as the writer was able to As has been noted above I have synony- determine, a transition zone modified by mized the subspecies arizonensis with the the presence of a considerable number of typical pallipes. I am of the opinion that southern forms. In view of the fact that Wheeler was misled by an incorrectly at higher levels Ramsey Canyon supports labelled specimen, to look for differences a magnificent stand of timber and in this which actually do not exist. I have made heavily wooded area there occur genera of a very careful study of the single type on ants commonly associated with Stigma- which the subspecies arizonensis was tomma, the writer was at first inclined to based. Wheeler noted six differences believe that the single specimen of arizo- which distinguished arizonensis from the nensis had in some way managed to reach a typical pallipes. It was (1) smaller level considerably below its normal nesting (length 4 mm.), (2) the sides of the head site. I am now convinced that a much were more nearly parallel, (3) the lateral simpler explanation is the correct one. -teeth at the insertion of the mandibles The whole matter becomes clear if we were smaller, (4) the sculpture was finer assume that the type of arizonensis is and more opaque, (5) the pubescence was actually a specimen of the typical pallipes shorter and lacking on the upper surface which, through mislabelling, became in- of the head, (6) the color was ferruginous. cluded with the material taken by Dr. As far as size is concerned the type of Mann in the Huachuca Mountains. In arizonensis is scarcely smaller than many this connection I wrote Dr. Mann who of the small workers which appear in the informs me that he has no recollection of nests of the typical form. Moreover, such having taken the type of arizonensis when small individuals have narrower heads he collected in Ramsey Canyon. This 6 AMERICAN MUSEUM NOVITATES [No. 1079

of course, is not conclusive proof and the inextricable manner in which the forms are fact that almost twenty-five years have intermingled. If we go further south, elapsed since arizonensis was described however, the matter becomnes much mnore adds to the chance for error. Yet I am understandable. As far as the writer has sure that all good field workers will agree been able to determine specimens comng when I say that a "find" of such an unusual from the southern coastal strip all show nature would produce a lasting impression. the characters of the larger, typical It is highly unlikely that if such an exem- pallipes. As one goes inland toward the plary field worker as Dr. Mann had dis- Piedmont there is an infiltration of the covered a Stigmatomma in the Huachucas smaller specimens while in the valleys at he would have failed to recall the circum- the foot of the mountains there is a pre- stances. Whether the above explanation ponderance of the form that Santschi has be correct or not the writer maintains that called wheeleri. At elevations of three arizonensis is not a valid form. We shall thousand feet or more (at least in North have to regard it as a synonym of pallipes Carolina) these small specimens are re- even if this necessitates extending the placed by the variant described in this range of the typical form to the Huachuca paper as montigena. The characteristics Mountains. of montigena show in a more extreme those My reasons for synonymizing the form degree of wheeleri. The funicular described by Santschi as the variety joints are very short, the clypeus is strongly projecting in the middle and the node of 'ltheeleri are drawn in large part from the ertain zo6geographical considerations of petiole is markedly narrow. It may vhich Dr. Santschi was not aware when seem ill advised to defend the status of .ie set up this form. The type material montigena and at the same time sink of wheeleri came from Colebrook, Conn., wheeleri since the latter form is obviously and was, apparently, collected by Wheeler, intermediate between montigena and the although the specimens were sent to Sant- typical pallipes. This is precisely the schi by Bequaert. In comparing these reason why I believe that wheeleri should specimens with others which Wheeler had not have been named. It is clearly a form sent him from Massachusetts, Santschi was produced by the intergradation of the able to draw up an imposing list of mountain-dwelling subspecies montigena differences. He, therefore, gave the and the lowland pallipes. Unlike the Connecticut material varietal status despite other two variants it has, as far as the the fact that twelve years before Wheeler writer has been able to determine, no range had commented on the variability of the where it is the only form present. I am typical pallipes in the Connecticut area. ready to admit that the structural char- As anyone who has collected this insect is acters of wheeleri permit a separation of aware specimens which come from the the intergrade from the other two sub- northeastern portion of the range are species but this distinction has a decidedly notoriously variable as to size. The limited application. If generally used it smaller individuals occurring in this region involves the splitting of nest series, par- have all the characteristics of Santschi's ticularly in the case of specimens coming variety wheeleri, a part of the type series from the northeastern states. This feature of which is in the collection of the M.C.Z. is perhaps less objectionable than the Yet the smaller forms occur in the same matter of the rank of wheeleri. It cannot areas, or for that matter in the same nests, properly be considered as a subspecies and as the larger ones. I seriously doubt that if it is to be named at all we shall have to anyone whose studies had been limited to employ another rank for its designation. the area within one The writer is completely opposed to the hundred miles of New use of York would be able to analyze the situation more than one infraspecific rank and successfully because for this reason, if for no other, I propose of the seemingly to drop the name wheeleri. 1940] REVISION OF STIGMATOMMA PALLIPES

Stigmatomma pallipes montigena, new Holotype (female), ergatotype and a subspecies series of paratypes of montigena deposited WORKER.-4.5-5 mm. in the collection of The American Museum Differing from the worker of the typical of Natural History. Additional paratype pallipes as follows: Head much narrower, the sides somewhat material in the collection of the Museum more evenly converging toward the occiput, of Comparative Zo6logy and the collection the occipital border slightly concave. All the of the author. This subspecies is based funicular joints except the first and last are upon a series of specimens taken by the notably broader than long, joints 2-5 almost twice as broad as long. The mandibles always author at Little Switzerland (elevation appear to have five double teeth, the outermost 3400 ft.) near Spruce Pines, North Caro- pair never being imperfectly divided or single lina. Other specimens were secured at as is frequently the case with the typical pallipes. Blue Ridge (elevation about 3000 ft.) In addition there is frequently a small tubercle between the large, basal tooth and the first about five miles east of Black Mountain, double tooth. Thorax more slender than in the North Carolina. I have also seen workers typical pallipes, the sides of the epinotum seen taken by Dr. P. J. Darlington on Mt. from above broadest at the middle. Basal face Mitchell and by Mr. Nathan Banks on of the epinotum slightly concave, more shining and much more lightly marked with transverse Greybeard Mountain in the same state. striae than in the typical pallipes. Node of the petiole seen from above much narrower. Clypeus with 9-11 teeth, of which seven form Stigmatomma pallipes oregonensis a rather strongly projecting central lobe which Wheeler is flanked at either side by a more or less divided lateral tooth. Ventral lobe of the petiole some- what larger than in the typical pallipes. Entire 1915, Bull. Amer. Mus. Nat. Hist., XXXIV, insect slightly more shining due to the smaller p. 389, Q 9. and shallower punctures. Body hairs finer, The size of the worker of oregonensis more even in length and more golden in color, particularly on the gastric segments. Color appears to be fairly constant with the usually lighter than that of the typical pallipes majority of the individuals measuring but there is considerable variation in the degree 5.5-6 mm. in length. The tendency to of infuscation. produce small individuals is less marked The female of montigena shows most of than in the typical pallipes, although it is the differential characteristics which mark not impossible to find workers which are the worker. There is, however, less differ- scarcely 5 mm. long. I find several of the ence in the proportions of the thorax. distinctions given in the original descrip- One point may be added in connection with tion of this subspecies somewhat confusing. a statement made by Santschi concerning If one selects individuals of comparable the female of wheeleri. According to size for comparison it is difficult to see Santschi the eyes of the female of wheeleri that the eyes of oregonensis are any larger are much smaller than those of the typical than those of the typical pallipes, nor is it pallipes. As the worker of montigena clear that the head of the first subspecies appears to show, to a more extreme degree, is shorter. The node of the petiole, seen most of the differences which were used to from above, appears to be definitely bulkier separate wheeleri from the typical pallipes, in oregonensis but this difference is clearly one might expect that the female of monti- shown only by the largest workers. On gena should have very small eyes indeed. the other hand there is very little likelihood Actually the eyes of the montigena female of confusing oregonensis with any of the appear to be no smaller than those of the other variants because of its unique mandib- typical form. I take it that Santschi was ular structure. As noted in the key the misled by the fact that the total number inner margin of the mandible of oregonensis of facets in the eyes of the female often is almost straight. The mandible narrows, varies so that by selecting suitable speci- of course, at the base of the large, apical mens it would be possible to set up what tooth, but the marked convexity of the appear to be striking differences in eye inner margin, which is present in all the size between individuals coming from the other subspecies, is lacking in oregonensis. same nest series. The antennal scapes of oregonensis are 8 AMERICAN MUSEUM NOVITATES [No. 1079 slightly longer than those of the other Park, Corvallis (H. A. Scullen); Forest Grove (M. C. Lane, A. C. Burrill) subspecies and the anterior edge of the Washington: Olympia (Kincaid), type locality clypeus is quite characteristic. The edge for the female of the clypeus is virtually straight with the British Columbia: Vancouver Island, Royal large flanking tubercles on the same level Oak (collector, J. T. D.) as the finer teeth which they enclose. The number of the fine, central teeth varies Stigmatomma pallipes subterranea, from six to nine. A similar condition is new subspecies found in the clypeal margin of the sub- The worker of this subspecies differs from that of the typical pallipes as follows: species subterranea but in the latter form The occipital border is more strongly im- the middle of the clypeus is usually slightly pressed in the middle; the posterior half of the convex and bears fewer teeth. The color head has the sides sloping inward more sharply. of the worker of oregonensis is very similar The six small teeth which occur at the middle of the clypeal margin are smaller and more to that of the darker specimens of the sharply set off from the flanking tubercles. eastern pallipes. In fully colored indi- The color is a clear yellowish brown without viduals the head and thorax are blackish any trace of infuscation. The sculpture is brown with the gaster and legs a clear, everywhere lighter and the whole insect more yellowish brown. shining. The pilosity is a little sparser, par- The size of the female of oregonensis is ticularly on the head and thorax. rather variable. Most of the specimens Described from fifteen workers taken by are the same size as the larger workers the author at Elmo, Kansas, on September but, in the same nest series, the length of 6, 1927. the female may vary from 5.5-7 mm. Holotype (worker) and a series of para- The cephalic characters which distinguish types deposited in the collection of The the worker of oregonensis are found also American Museum of Natural History. in the female. The male of oregonensis Additional paratypes in the collection of is unknown. the Museum of Comparative Zoology and The material belonging to the above the collection of the author. Besides the subspecies which the author has been able type material I have seen three workers to examine comes from the following taken by W. P. Hayes at Winfield, Kansas, localities: and a single specimen from Shoal Creek, Oregon: Marion County (P. J. Schmitt), type Texas (Wheeler collector?), which appears locality for the worker; Duncan, Blod- to be an intergrade between subterranea gett (P. J. Darlington); Benton-Lane and the typical pallipes.