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Show THE MOUND-BUILDING PRAIRIE ANT A MOST INTERESTING DESCRIPTION OF THIS INDUSTRIOUS LITTLE INSECT jH AND ITS CAREFULLY PLANNED PRAIRIE NEST. jfH Bjr George A. Decs. , H In crossing the palrles of a large part of the Western States, the traveler's trav-eler's attention is frequently drwn to the gravel-covered mounds that skirt the railways and wagon roade. Located in the centor of cleared circular circu-lar areas, they stand out prominently, breaking the grassy surface. Theee mounds dot the slopes of ravinee, the banks of stream, and nooks and flats between cliffs and ridges. They occur along travelled street and sidewalks. In corrals, and In door-yards. door-yards. They aro present in fiolds of wheat and alfalfa, In splto of the plowing and disking. They possessed the prairie before the farmor came, and they remain in splto of his operations. oper-ations. The ant whoso Industry has made these mounds, with their clcan-swopt clcan-swopt dooryards, clings tenaolously to the house which It has built and, so often as tho roof is destroyed, laboriously labor-iously rebuilds It. The neots aro various elzes and heights, ranging from nine to twenty-four twenty-four Inches. The clearing surrounding surround-ing the mound Is level, absolutely devoid de-void of vegetation, and usually ha the mound exactly in the centor. The slie of the clearing ranges from nine to twenty feet and in one Instance extended for forty-five feet Tho ante cannot tolerate the presence pres-ence of vegetation near their mounds and the workers clear it away by use of their well-adapted mandible. Thoy doubtless find that vegetation Is an obstaolo to their going and ooming; that it affords concealment to their enemiee: retains moslture aftor a rain, thus favoring the growth of injurious fungi; that its root penetrate tho chambers of their nests and, decaying, decay-ing, form passageways for the entrance en-trance of water. The dexterity r.nd eaee with which the worker handle the pebbles wherewith where-with they covtr their homes is a source of constant lnterert and surprise, sur-prise, A worker will eUe a pebble with outstretched mandibles and. with head elevated, holding It wet) to the front oarry It over the rough surface sur-face to the very top of the monnd without once stopping to rent In no case does one worker help another that happens to havo undertaken too heavy a load. We have en such individuals individ-uals struggling vainly at the baso while their comrades par unconcernedly unconcern-edly up and down all about them. In many of tho mounds the ants go and come, through one opening. In others they havo two or three such passageways, and in one excoptlon-1 ally large mound ths occupants had eight opening. These gateway are usually about one-third from the base to the summit of the mound. At night or on the approach of a raln-Btorm, raln-Btorm, the opening aro closed with material similar to hat of which the mound-covering Is composed. During the summer the ant begin to close them shortly before sunset and open them between eight and nine o'clock In tho morning. So perfect is tholr workmanship that even close examination exami-nation does not really show whero the openings havo been. The force of workers that does the night closing Is small, but when a storm is rapidly approaching, the number Is greatly Increased that the work may be quickly quick-ly completed. In the morning as soon as the gates are opened, the working force Is out and busily engaged. It returns to the nest shortly boforo noon and remains inside until tho hottest part of tho day is past, then they como out and work until evening. On cool, cloudy days the midday return to the nest is omitted and tho forco continues In tho field during tho whole day. Tho morning and noon hours aro probably omployed In caring car-ing for and enlarging the interior of the nest The Interior of the mound Is honeycombed honey-combed with chambers and galleries. Tho ohambers vary from ono to three inches In diameter and from one-half to one Inch In height The connecting connect-ing gallorles havo a uniform diameter of about S-8 of an Inch. Sealod and unsealed etoreroome filled with seeds occur throughout the neat Larvae, pupae, and young ants oocupy many of the chambers. Seede of various kinds aro carried by the worker Into the neet TM BBBS hulls are torn off, carried out and BBBZ dumped at ono eldo of the cice.rln SBBS and tho plump, sound seeds stored BBBS away In the storerooms. BBBa The mound-building prairie ant BBBa shows throe diatlnot classes of Individ.- BBBJ uals tho queens (fertile females.) BBJ males, and workers (sterile females.; BBJ Queens and males form a compare- BBS tlvely small portion of the colony jH while the workers In a nest have bean iBBX known to numbor 10,000. BBS Although theso ants are larger than IBBB most species and have two of the most JBBX formidable weapons known Among In- mBI sects largo, pointed mandible an fWaVs. flBfcl M 1 no tr.-o upper lsxecte aro woAcstb : left BBS lcrtre? is a fettiie tbtxtSa o? qc.WJii VBa ai'rl light lover is ( malct m most efficient stings they are not 'sS quarrelsome, and fight only in self- -9BJ j defence. So peaceably inclined aro SBS they that other species of ants are BBS allowed to como into their clearings BBS and throw up their tiny cresont-ohap- BBX cd mounds of earth, and even to at- H tack and chase such thoughtless Urn "mound-builders" as happen to pass BBS too near them. Indoed, they carry H this peaceful disposition to a point BBJJ whero they permit the common tor- ' mite and somo species of ants to live BBS with them in tho chambers of thejr lM I nests and to partake of their stored BBJ food. I These ants have come to be con- taBS sldercd injurious Inlets, not through smBm lncrcano In numbers, but rather BjBjj through their close contact with man flH resulting from his conversion of the SB prairies into cultivated fields. M The ant colonics are too scattering B ' to materially decrease tho yield of any Bfl i crop; they are chiefly troublesome a SBJI J an obstacle to harvesting. JBSl I To attempt to mow through or over VjH I thorn would choke tho machinery and BV ruin tho cutting-edge of the siokle. H j Should a driver have such trouble in yB i passing over a mound it would be BBS I most unwise for him to stop and try jK I to adjust his machinery, for such & BSfl I disturbance would bring tho ants forth BBj I In angry swarms, each individual eag- BSB I or to do her utmost to repel tho In- BBS j vadcr. Every one that suaceeded in fBH gctttng man or beast would solze v clothing, hair, or skin between her BSfl mandibles, curve her adboraen down- nHJ ward, and deliver a thrust quite as H painful in result as tho sting of bum- BSfl blobeo or yellow-Jacket. BSfl In tho dooryard the ants not only BBS) render tho lawn unsightly with their BVM mounds but unhesitatingly attaok the BSfl careless child who walks over or plays Bn about their nest " BB |