358 



AMERICAN HOMES AND GARDENS September, 1907 



New Ant Lore 



By George Bullock 



HE red weaver-ant, which is wide-spread in 

 the tropical Indies, the Malay Archipelago 

 and Polynesia, inhabits globular leaf-nests in 

 colonies. Such a nest is formed by joining 

 together the edges of adjacent leaves with 

 silky webs. It is not very easy to ob- 

 serve the little creatures at their work, as 

 they endeavor to scare off every intruder by death-defying at- 

 tacks in force. An observer, Dr. F. Doflein, who, in a high 

 tree-top in Ceylon (defying the itching biting), made a rent 

 in such a nest, saw how a detachment separated itself from 

 the hundreds of little defensive animals and sought to repair 

 the rent. The female working-ant digs the sharp claws of her 

 two pairs of hind legs into the siuooth leaf, the forelegs and 

 antennae high in the air, and the masticators open for biting. 

 A repair detachment, drawn up in a straight line beside each 

 other, grasps the edge of the other leaf in their jaws and 

 draws it nearer to the edge of their own leaf, while the little 

 creatures, fixing the claws of all six feet in the leaf, carefully 

 set one foot round the other backward, and at the same 

 time thereby draw the edge of the further leaf nearer. Other 

 female working ants hurry hither, biting off the still clinging 

 remnants of tissue, and bearing them to the ends of leaves or 

 of branches, where, simultaneously letting go, as if at word 

 of command, they cast to the winds the conjointly detached 

 shreds. After much exertion the repairers brought the 

 leaf edges so close together that the actual work of weaving 

 could begin. There now appeared female workers with 

 larva? between their jaws, and moved the pointed end of the 

 larvas back and forth, from edge to edge, each time pausing 

 a little, that the spinning thread that was being detached 

 from the larvae might take hold upon the edge of the leaf. In 

 one of the accompanying figures can be seen the tongs-like, 

 larvae-clasping jaws of the weavers, who were now in the 

 manner described covering the rent with a thick, silky web. 

 The web is so tough that it may be cut with scissors. The 

 weaver-ants make use, then, in its manufacture of their 

 larvae at once as distaffs and as shuttles. They are the only 

 animals among whom, so far, the use of a tool has been 

 observed. In the construction of the globular leaf-nests the 

 presence of cochineal-insect colonies is especially attractive, 

 as the excretions of these creatures are a real treat to the ants. 



If we betake ourselves from India to South America, 

 here, too, are found ants that are good at weaving. More 

 remarkable, however, there are the leaf-cutter ants, which 

 lay out, manure, weed and reap regular fungus-gardens. The 

 leaf-cutter or dragging-ants are so named from their attack- 

 ing in dense swarms shrubs and bushes, cutting out pieces of 

 leaves and dragging them long distances into their nests, 

 always built covered, where the pieces of leaves furnish the 

 subsoil for fungus-gardens. These female leaf-cutters often 

 in a short time entirely strip shrubs and saplings of their 

 foliage. The cutting out of the pieces of leaves they accom- 

 plish by turning upon their hind legs as a center and roundly 

 cutting out a piece of leaf, as with a pair of scissors, with 

 their saw-like jaws pressed together. Though the pieces of 

 leaves often have four times the length and several times the 

 weight of the ant, they are yet conveyed over paths which 

 take the little creatures hours to travel. The paths unite 

 in a highway, where from all sides laden working-ants con- 

 verge and present a peculiar appearance — rows of curiously 

 formed pieces of leaves totterlngly moving forward, under 



which the bearers almost disappear. These dragging-ants 

 are eminently skilful road- and vault-engineers. With their 

 jaws they tear off in the course of the way to be built one 

 small bit of earth after another, and pile them right and 

 left in a wall; elsewhere they vault the way over till it be- 

 comes invisible. Certain female workers hurrying, without 

 employment, hither and thither upon the way look after 

 the improvement of the roads. They form in a certain 

 measure a flying-column, which has to remove the obstacles 

 to traffic often found upon the way. 



The fungus-raising ants (of which there are several kinds) 

 build their nests in cavities underground, under stones, 

 roots of trees, the bark of Inwardly rotting, fallen tree- 

 trunks — in fine, everywhere where either they are well cov- 

 ered by nature externally, or where they themselves, by 

 means of piling up leaves and twigs, can manufacture a pro- 

 tecting covering. On the inside of the nests Is found merely 

 a gray, sponge-like. Incompact mass, which extends up to 

 two yards In length and several handbreadths In height, 

 but never reaches to the walls of the cavities. In the spongy 

 growth, which abounds in apertures, the ants actively work, 

 and their eggs, larvae and pupae lie scattered around. What, 

 however — contrary to all expectation — are not discovered in 

 the nest are the quantities of pieces of leaves brought in, 

 whose loss bushes and shrubs are mourning. Have the ants 

 eaten the pieces of leaves? No; for the creatures have been 

 kept Imprisoned, and they prefer going hungry to feeding on 

 leaves. When, however, they were given something from 

 the incompact, gray, flocculent mass of fungus, then they at 

 once began to use this "free estate" in the laying-out of a 

 fungus-garden, to which they gave the chopped-leaf ma- 

 terial as fostering subsoil. The pieces of leaves are cut up 

 into many little bits by means of chewing and pressure. The 

 bits are thoroughly soaked, kneaded and shaped, and finally 

 inserted in the fungus-garden as systematically as a mason 

 presses down into Its bed the last brick into a new, just- 

 laid course. 



Ants, as is well known, sometimes desert their homes. 

 When, in consequence of unwelcome disturbances, the ants 

 leave their nest, then the fungus-garden is taken along. It is, 

 as manifold experiments have Indubitably shown, their only 

 source of nourishment. They eat the little globules, rich In 

 plasma, which appear to the naked eye merely as white dots 

 on the surface of the mass of fungus. By means of minutely 

 exact experiments it is established that only this one fungus, 

 and no others, grovi's upon the carefully constructed fos- 

 tering-soil. Foreign material is weeded out, while an enor- 

 mous number of the smallest female working-ants continually 

 removes the foreign filaments and spores of fungus acci- 

 dentally dragged in, which might overgrow the garden. We 

 here have before us, then, pure cultures, carried out by ani- 

 mals, of a wholly definite fungus. 



These ants too, are infected by the modern colonizing 

 spirit. When a queen of the ants burrows into the earth after 

 the marriage flight and plants a new colony, shut off from the 

 outside world, occupied only with egg-laying and the breed- 

 ing of her young, she has nevertheless then brought with her 

 from the old nest "free estate" for the laying out of a 

 fungus-garden. Of the extraordinarily remarkable proceed- 

 ings at the planting of such a colony. Dr. Jakob Huber-Para 

 recently published his observations made upon the genus 

 Atta sexdens in several series of experiments. We see In 



