UC-NRLF 54 SIS F-HOUKC>ERIE: CHAPTERS ON AN MARY TREAT THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID HAEPER'S HALF-HOUR SERIES. 3?aper. 1. The Turks in Europe. By Edw. A. Freemau.fO 15 2, 3. Tales from Shakespeare. By Chas. and Mary Lamb. Comedies, 25 cts. Tragedies, 25 cts. 4. Thompson Hall. By Anthony Trollope. Ill's. 20 5. When the Ship Comes Home. By Walter Be- sant and James Rice ........... . ............... 25 C. The Life, Times, and Character of Oliver Cromwell. By E. H. Knatchbull-Hugesseii ____ 20 7. Early England. By F. York-Powell .......... 25 8. England a Continental Power. By Louise Creighton ...................................... 25 9. Rise of the People, and Growth of Parliament. By James Rowley, M. A ........................ 25 10. The Tudors and the Reformation. By M. Creightou, M. A ................................ 25 11. The Struggle Against Absolute Monarchy. Bv Bertha M. 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By Wilkie Collins. .. 20-'. 26. Cooking Receipts. From Harper's Bazar, ... 25 27. Virginia. A Roman Sketch .................. 25 Harper's Half -Hour Series. 28. The Jews and their Persecutors. By Eugene Lawrence $0 20 29. The Sad Fortunes of the Rev. Amos Barton. By George Eliot 20 30. Mr. Giflil's Love Story. By George Eliot 20 81. Janet's Repentance. By George Eliot 20 32. The A B C of Finance. By Simon Newcomb.. 25 33. A Primer of Mediaeval Literature. By Eugene Lawrence 25 34. Warren Hastings. By Lord Macaulay 25 35. Addison. By Lord Macaulay 25 3(5. Lord Clive. By Lord Macaulay 25 37. Frederic the Great. By Lord Macaulay 25 38. The Earl of Chatham. By Lord Macaulay 25 Hi). William Pitt. By Lord Macaulay 25 40. Samuel Johnson, LL.D. By Lord Macaulay. . 25 41. Hampclen.— Burleigh. By Lord Macaulay 25 42. Sir William Temple. By Lord Macaulay 25 43. Machiavelli.— Walpole. By Lord Macaulay. . 25 44. Milton. — Byron. By Lord Macaulay 25 45. My Lady's Money. Related by Wilkie Collins 25 46. Poor Ze'ph \ By F. W. Robinson 20 47. Shepherds All and Maidens Fair. By Walter Besant and James Rice 25 48. Back to Back. By Edward Everett Hale 25 49. The Spanish Armada for the Invasion of Eng- land. 15S7-15S8. By Alfred II. Guernsey 20 50. Da Capo. By Anne Isabella Thackeray 20 51. The Bride of Landeck. By G. P. R. James. . . 20 52. Brother Jacob.— The Lifted Veil. By Geo. Eliot 20 53. A Shadow on the Threshold. By Mary Cecil Hay 20 54. David's Little Lad. By L. T. Meade 25 55. Count Moltke's Letters from Russia 25 56. Constantinople. By James Bryce 15 57-59. English Literature Primers. By Eugene Lawrence: 57. Romance Period.— 58. Classical Period. — 59. Modern Period each 25 60. Tender Recollections of Irene Macgillicuddy. 15 61. Georgie's Wooer. By Mrs. Leith-Adams 20 C2. Seven Years and Mair. By Anna T. Sadlier. . 20 03. A Sussex Idyl. By Clementina Black 25 Harpers Half -Hour Series. 3 64. Goldsmith.— Bunyan.— Madame D'Arblay. By Lord Macaulay $0 25 65. The Youth's Health -Book 25 66. Reaping the Whirlwind. By Mary Cecil Hay. 20 6T. A Year of American Travel. By Jessie Beu- ton Fremont 25 68. A Primer of German Literature. By Helen S. Conant 25 69. The Coming Man. By Charles Reade 20 70. Hints to Women on the Care of Property 20 71. The Curate of Orsieres. By Otto Iloqiielte 20 72. The Canoe and the Flying Proa. By W. L. Alden 25 73. Back to the Old Home. By Mary Cecil Hay. . 20 74. The Lady of Launay. By "Anthony Trollope. 20 75. Sir Roger de Coverley. From The' Spectator . . 25 76. Pottery Painting. By John C. L. Sparkes 20 77. Squire Paul. By Hans Warring 25 73. Professor Presseusee. By John Esten Cooke. 25 79. The Romance of a Back Street. By F.W. Robinson 15 80. Behind Blue Glasses. By F. W. Hacklnnder.. 20 81. Recollections of Rufns Choate. E. P. Whipple. 15 82. Daisy Miller. By. Henry James, Jr 20 83. A Primer of Spanish Literature. By Helen S. Conant 25 84. A Dark Inheritance. By Mary Cecil Hay 15 85. The Vicar of Wakefield. B~y Oliver Gold- smith 25 80. Stories from Virgil. By A. J. Church 25 87. Our Professor. By Mrs. E. Lynn Linton 15 88. The Sorrow of a Secret. By Mary Cecil Hay.. 15 89. Lady Carmichael's Will and other Christinas Stories. By Mary Cecil Hay and others 15 90. 'Twas in Trafalgar's Bay. By Walter Besant and James Rice 20 91. An International Episode. By II. James, Jr. 20 92. The Adventures of Ulysses. By Charles Lamb ' 25 9B. Oliver Goldsmith's Plays 25 94. Oliver Goldsmith's Poems 20 95. Modern France. By George M. Towle 25 Harper^s Half -Hour Series. 90. Our Village. By Miss Mitford $0 25 97. Afghanistan. By A. G. Constable ] 5 98. John. By Thomas W. Knox 20 99. The Awakening. By Mrs. Macquoid 15 100. Ballads of Battle and Bravery 25 101. Six Months on a Slaver. By E. Manning 20 102. Healthy Houses. By Fleeming Jeukiu. Adapted by George E. Waring, Jr 25 103. Mr. Grantley's Idea. By John Esteu Cooke. 25 104. The Four Georges. By W. M. Thackerny .. . . 25 105, 106. The English Humorists. By W. M. Thack- eray. In Two Numbers each 25 10T. Half-Hour History of England. By Maudell Creighton, M. A 25 108. Lord Bacon. By Lord Macaulay — 25 109. My Sister's Keeper. By Laura M. Lane 20 110. Gaspard de Coligny. By Walter Besant. M.A 25 111. Tales from Euripides. By Vincent K. Cooper 20 112. The Task. By William Cowper 20 113. History. — Hallam's Constitutional History. By Lord Macaulay 25 114. The Lay of the Last Minstrel. By Sir Wal- ter Scott 20 115. Marmion. By Sir Walter Scott 25 116. The Lady of the Lake. By Sir Walter Scott. 25 117. The Lover's Tale. By Alfred Tennyson 10 118. Wassail. By Colonel Charles Hamley 20 119. Modern Whist. By Fisher Ames 20 120. The Rivals and the School for Scandal. By Richard Brinsley Sheridan 25 121. Holidays in Eastern France. By M. Betham- Ed wards 25 122. Labor and Capital Allies— Not Enemies. By Edward Atkinson 20 123. Chapters on Ants. By Mary Treat 20 124. The Bar-Maid at Battleton. By F. W. Rob- inson 15 CHAPTERS ON ANTS BY MARY TREAT NEW YORK HARPER & BROTHERS, PUBLISHERS FRANKLIN SQUARE 1879 Entered according to Act of Congress, in the year 1879, ty HARPER & BROTHERS, In the Office of the Librarian of Congress, at Washington. F-7T7 PKEFAOE. THE "Chapter in tlie History of Ants" was originally contributed to Harper's New Monthly Magazine. It grew out of my ob- servations of the habits of the slave-making ants (Formica sanguinea) of New Jersey. The paper on " The Harvesting-Ants of Florida " was published in Lippincotfs Mag- azine, and its appearance in this form is due to the kind permission of the proprietors of that publication. M.T. Vineland, N. J. CONTENTS. PAGE I. SLAVE-MAKING ANTS 11 II. HARVESTING- ANTS OF FLORIDA 72 ILLUSTEATIONS. PAGE Slave-making Ant 12 Ant-nest, with Underground Passages 18 Larva, Cocoon, and Pupse of Red Ant 20 Front View of Red Ant's Head, showing An- tennae and Mandibles 26 Honey-sac and Stomach of Red Ant 27 Ants attacking Larva 32 •External Anatomy of Red Ant 36 Nervous System of Red Ant 36 Queen of Slave-making Ants 45 Excavating an Ant-hill 73 Soldier 76 1. Worker Major; 2. Outline of Head of Worker Major; 3. Outline of Body of Worker Minor 81 Queen : Side View, showing Peculiar Confor- mation of the Thorax 83 Mandibles of the Harvesting- Ant . . .88 TWO CHAPTERS ON ANTS. I. SLAVE-MAKING ANTS. THE family of ants is ranked the highest among insects. The geologist tells us that this family does not date very far back in the world's history. The lowest forms of the hymenoptera appear in the Jurassic pe- riod, but the ants do not make their appear- ance until the tertiary period, while other orders of insects have been found in the car- boniferous era, and some even in the Devo- nian formation. The anatomist shows us that the nervous system of the ant is highly organized, that the cerebral ganglia are well developed, evincing an intellectual superiority over the rest of the insect world. Eminent naturalists, especially in Europe, have devoted almost their entire lives to the study of these interesting creatures, but SLAVE-MAKING ANTS. 13 in our own country observers have not had the time or patience for such exclusive at- tention to this family ; hence there is much conflicting testimony, especially with re- gard to the habits of the slave-making spe- cies— Formica sanguined. In the following pages I shall give a brief account of the wonderful wars and con- quests over other tribes made by a powerful colony of this slave-making species. It is the result of several weeks' close observa- tion, to the exclusion of all other work, com- mencing the 1st of July and extending into August. The nest was in a grove that surrounds the house, and must have contained several thousand working inhabitants. About fifty feet from the nest of red slave-makers was a nest of black ants (Formica fusca), and I should judge this colony to be fully as large and strong as that of the red ants. Externally the two nests did not differ very much. The red ants raised a slight mound, while the blacks had simple excava- tions about the roots of an oak-tree. These two nests had been under my observation for at least three years, and yet I more than half doubted that these reds were really slave-makers. The blacks were my favor- 14 TWO CHAPTERS ON ANTS. ites, being so much more quiet and steady in their habits. A black scarcely ever at- tempted to bite my hand, even if I used him quite roughly, but the reds would resent a slight provocation. I have had my gloved hand almost covered with the angry fellows, biting and holding on to my glove, simply because I uncovered one of the closed en- trances to their dwelling. I have some- times allowed one to bite my hand, and found it could hurt considerably, and that it left a small purple spot where its mandi- bles had pierced. It is stated in scientific works that colo- nies of the red ant often move, and carry their larvae and pupse to other nests. Up to this summer I should have concurred in the above statement, as I had several times en- countered a trail of red ants carrying larvae and pupae, and had traced the trail from its starting-point, and found only red ants emerging from excavations among rubbish, and so concluded that these ants were sim- ply moving ; but a closer and more careful study of their habits has convinced me that this opinion was founded on superficial ob- servation. On a sultry afternoon, the first day of July, I was lazily sauntering in the grove, SLAVE-MAKING ANTS. 15 when, on looking down, I found, to my sur- prise, that I was in the midst of a battle- field. A powerful army of red ants had in- vaded the dominions of the black colony which for three years past I had had a kind of supervision over. I had often brought plants covered with aphides — the immortal Linnaeus called these aphides the ants' cows — and stuck the plants into the earth around their dwelling, and had given them sugar, and had driven and carried toads from their nest which were devouring them. In short, I had become very much interested in and quite attached to this colony, but I was pow- erless to aid them now. I could only look on in wonder and astonishment. A yard or more around the foot of the tree the battle was raging, and no place for the sole of my foot without crushing the combatants. I found in every instance a red ant pitted against a black; sometimes two red ones against one black, in which case the black was soon despatched. For three hours I watched the conflict; all around me the combatants locked in a close embrace, rolling and tumbling about, never separating until one was killed, and often the dead victim had fastened with so firm a hold on his adversary that it was with the 16 TWO CHAPTERS ON ANTS. utmost difficulty that he could free himself from his death-grip. The sun went down, and the gathering darkness compelled me to leave my post of observation ; but as long as I could see, the conflict was as fierce as when I first beheld it. I now picked up several of the war- riors, but so intent were they in their ter- rible struggle that my handling did not di- vert them in the least. I carried several pairs into the house, placed them under a large oval glass (the cover of a fernery) on a marble-topped table, and watched the con- flict. I found I had ten black and ten red war- riors, not engaged in a general me!6e, but each intent upon killing his own adversary. It was fully an hour before the first warrior was killed — a red has at last dispatched his black antagonist, and not satisfied with kill- ing him, he tears his legs from his body and severs his antenna. After convincing him- self that he is really dead, he looks around at the other warriors which are still closely locked in their dreadful embrace, and now he hurries from one couple to another, as if to see where his services are most needed. He finds a couple whose struggles are near- ly over — a black is fastened with a death- SLAVE-MAKING ANTS. 17 grip to liis adversary's foreleg. The red hero soon severs the head from the black soldier, and leaves it hanging to the leg of his dying comrade. He now goes to anoth- er conple who are still fiercely contending ; he seizes the black, and now all three roll and tumble about together; but the black is soon killed, and, as in the other case, his mandibles are locked on his adversary's leg. But this time our hero does not sever the head from the black soldier, but leaves his comrade to free himself as best lie can, while he goes to the assistance of a third less fortunate brother, where the black seems to have the better of his antagonist. Here a long struggle ensues, and now an- other red soldier has despatched his oppo- nent, and he conies to the struggling three, moves about them in an excited manner, with his mandibles stretched wide apart, waiting his opportunity to fasten them on the black ; he finds his chance, seizes him between the thorax and abdomen, and sev- ers the body in two; but the dying black does not relax his hold of the first antago- nist, and they die together. I now leave the fierce combatants for the night. In the morning I find that every black is killed, and four red soldiers are 2 SLAVE-MAKING ANTS. 19 dead, and two others cannot long survive. The legs and antennae and mutilated bodies of the dead warriors are strewn about, ev- ery fragment showing conspicuously on the white marble. Out of the twenty, fourteen are dead and two nearly lifeless— only four have survived. I put some drops of water and moistened sugar under the glass for the surviving heroes : two find tbe water and. driuk. I now repair to the battle-field. The struggle is over: not a black to be seen, but a column of the red invaders is emerging from a large cavity that leads to the numer- ous galleries and underground chambers of these industrious blacks, and each invader is carrying a larva or pupa. I follow the column, wbich is from four to five inches in width, to the nest of reel ants before men- tioned. There is a wide opening in the side of this nest, down which they all disappear and leave their burdens, and again start for more plunder. All day long these powerful marauders are engaged in this work. They carry a larva or pupa carefully, and drop it on beiog disturbed. But what does this mean? Every little while a red warrior comes out with a black bundle, which he carries as carefully as he does the pupa or larva. I stop him to inquire into the mat- TWO CHAPTERS ON ANTS. ter; he drops his bundle, which immediate- ly unrolls, and lo ! it is a lively black ant, apparently unhurt, and, to my eye, 110 way different from the warrior with whom he wras so fiercely fighting. The books which I have read on the sub- ject inform me that " the red ants carry the pupae and larvae of the blacks to their nest, where they rear them for slaves, but they never capture the adult ant, for it would LAliVA, COCOON, AND PUP^E OF KED ANT. not stay in the new home if they did." But these ants certainly carried a great number of adult blacks to their nest, and I am quite sure they did not run away, but stayed and helped to nurse and feed the larvse. I capt- ure several of the red marauders with their victims, and place them under the glass. The reds now pay no attention to the blacks, SLAVE-MAKING ANTS. 21 but simply try to make their escape. I take larvae and lay them on a leaf, and put them under the glass also, and place moistened sugar in their reach. Very soon the blacks are feeding the helpless larvae. I remove the glass cover; the reds immediately run away, but the blacks stay, and continue to sip the moistened sugar and feed the young. I hold a magnifying -glass over them, and find the little larvae raise up their heads and open their mouths to be fed, very much like young birds. I now take the larvae, togeth- er with the nurses, and place them near the nest of red ants. I soon lose sight of the nurses, but the larvae are quickly taken into the nest by the red soldiers. By this time I have become so much in- terested in the red warriors, which I had heretofore rather avoided, that I resolved to devote my time to them, so I keep a daily record of their behavior. This record would be much too long for a magazine article, so I will make extracts from it. On the 3d and 4th of July the soldiers were very quiet, scarcely one to be seen, as if they were resting after their great raid of the 1st and 2d. On the evening of the 4th the blacks close the large main entrance through 22 TWO CHAPTERS ON ANTS. whicli the larvse and the pupae had been carried, and compel all the inhabitants to go in and out through another smaller door. While this entrance is being closed, two or three of the red soldiers stand just within the door-way and help to arrange the sticks which the blacks bring. Occasionally a red soldier which has been meandering about the premises comes to the nearly closed en- trance as if he would like to pass in ; imme- diately the antenna of one of the guard within is thrust through a small opening, and the one outside touches the antenna with his own, and then walks away and passes through the side door. After the entrance is closed I remove the covering ; this makes a great commotion among the soldiers; a large number rush out and run about in an excited manner. Finding nothing on which to vent their rage, they soon become quiet ; some return within, but a good number stay out and as- sist the blacks in reclosing the entrance. First they bring sticks from an inch to three inches in length and lay them across the opening, not in any regular order; often the end of one of the sticks is pulled in by those within, and the other end left sticking out. All sorts of material is brought and piled SLAVE-MAKING ANTS. 23 on to the sticks — pieces of dried leaves, and a butterfly's wing nearly two inches across, small pebbles and clumps of earth, and one brings a cherry-stone ; now a red soldier has found a piece of anthracite coal an inch in length and half an inch in thickness ; it lies nearly two feet away from the entrance ; he walks over and around it, and tries it with his mandibles as if taking its dimensions; he leaves it, and I lose sight of him among the busy toilers ; but very soon a large force of workers, both black and red, have sur- rounded this piece of coal; it is jagged and irregular in outline, thus affording places for the workers to fasten their mandibles. They move it a few inches, and now a tuft of stiff grass is in the way ; they drop the coal, and some pass over and others around the tuft; back they come and again seize it, but evidently the workers are of two miuds ; a part of them are determined to lift it over, and the others are equally deter- mined to take it round the grass on a com- paratively smooth road. After several in- effectual attempts to lift it over, they final- ly give up and join the others in taking it round. At last the feat is accomplished; this great weight is placed over the en- trance, as if to hold the other material in 24 TWO CHAPTERS ON ANTS. place, and to prevent another such catastro- phe— the sudden sweeping away of their work. And I respect their industry and courage sufficiently to leave them for this evening in their imaginary safety. Toward noon of the next day the blacks open the large entrance, dragging the mate- rial with which it is closed to one side ; and now the soldiers come out in full force, and march in a straight line to a spot about thirty feet distant ; here they diverge, and seem to be hunting over the ground; soon they find a small colony of blacks. The greatest excitement now prevails among the invaders ; some are passing down the main entrance, while others are rushing about with extended mandibles prepared for con- flict ; but the blacks are escaping from an- other opening a few inches distant, not try- ing to defend their young in the least. Very soon the marauders emerge, each with a lar- va or pupa. Those outside, seeming satis- fied that there will be no battle, quiet down and join the ranks in ravaging the nest. In less than an hour the spoils are all taken ; and the marauders, not satisfied in sacking so small a settlement, again form in line and march directly to another colony a few feet beyond the one they have so recently plun- SLAVE-MAKING ANTS. ZO dered.* They go so directly to this spot that it looks as if it must have been a precon- certed plan. This colony also proves to be a small one, and the inhabitants all flee, leav- ing the young to be captured. In less than two hours the spoilers have transferred the young to their own nest ; and new, appar- ently satisfied with their day's work, they make preparation to close the entrance — the blacks are clearing the passages which their masters have littered while carrying in their booty. As soon as the passages are cleared, a large force is engaged in closing the entrance, and this proves to be a perma- nent closing. About the same hour, for sev- eral days in succession, the blacks continue to pile material on and around this closed door; but only a few inches distant from, this a small opening is being greatly en- larged, which leads to several different gal- leries. I supply the ants with coarse granulated sugar ; they immediately commence to carry * grain by grain to their storehouse. Occa- sionally I notice that an ant carries a grain opposite to the nest and drops it, and then returns to the sugar and takes the next to the nest. I moisten the end of my pencil and pick up the discarded grain, and find it 26 TWO CHAPTERS ON ANTS. is sand. I now mix sand and sugar togeth- er ; the sand is left or thrown away, the su- gar only is taken, to the nest. Some observ- ers are inclined to think that ants do not store up food, and everything that is taken FRONT VIEW OP RED ANT'S HEAD, SHOWING ANTENNA AND MANDIBLES. to the nest is for building purposes. If this were true, the sand would not be discarded. I dissolve sugar with a few drops of wa- ter, and place it on an oak leaf; a large num- ber of black ants, and a yellow species about the same size as the blacks, surround the edge of the sirup, jostling and crowding one another, and some that cannot find a place on, the leaf mount the backs of the others SLAVE-MAKING ANTS. 27 and reach down to obtain a share. These are the nurses that feed the larvae. Their honey-sacs soon round out almost to burst- ing, and now they go thus heavily laden to HONEY-SAC AND STOMACH OF RFJ> ANT. the nest. I notice at the entrance through which they pass a number of red soldiers stationed like a guard, with tbeir heads thrust out, acting as if they would like to stop this line of honey-bearers ; they touch them with their antenna?, and sometimes one puts his forefeet against the shoulders of a nurse, but uses no real violence to detain her. Most of the nurses pass in regardless of these demonstrations, but occasionally one stops and puts her mouth to the soldier's, and feeds him in the same way she does a larva. These may be young soldiers which the nurses are about weaning, but they are so old that I can see no diiference in their looks or general behavior from the rest. 28 TWO CHAPTERS ON ANTS. Huber and other observers state that the nurse assists the young ant to escape from its pupa case, and feeds it for several days thereafter. But it is quite remarkable that a red soldier seldom partakes of the sirup or honey from the leaf, yet he often takes grains of sugar to store away, and will assist in taking a large lump to the nest. The sluggish oak moth (Dryocampa sena- toria) afforded the ants a rare harvest. This moth deposits her eggs on the underside of the oak leaf, and she is so sleepy during the day that she will not stir when the leaf is picked from the tree, and she will even sub- mit to being drowned without a struggle, rather than make the effort to rouse up and fly. So, on throwing one of these moths near the nest, it is soon surrounded with ants, and before it fairly awakens several pairs of man- dibles are fastened so firmly on its body a?id head that its feeble struggles are of no avail. These moths are always taken into the nest head -first; several times I have turned a moth round just as the ants reached the en- trance with it, but they would immediately turn it head-first, seeming to know as well as I did that this was the only way that it could be carried through the narrow pas- sage. SLAVE-MAKING ANTS. 29 But they do not seem to manifest so much reasou iu taking an earth-worm to the nest. Several red ants are coming on a gravel- walk with a worm about three inches in length ; they move along the walk very well indeed, all working in concert ; but soon they reach the border of dwarf iris, and are brought to a stand-still by making a loop of the worm round a stem of iris, about the same number of ants pulling at each end, neither party knowing enough to let one end drop. They try to raise it over the plant, which is about six inches high ; when they get nearly to the top, something always happens to bring it down to the ground. This is repeated full twenty times ; at last the strongest party are at one end, and now they soon pull it round the iris, and quickly disappear with it in the nest. But the most remarkable feat of this kind was performed by another colony of ants — F. schanfussii — a trifle longer but more slen- der than F. sanguinea. It has a black head and abdomen and a russet-brown thorax, and seems to be the most intelligent species which I have observed. This species also has its nest in a border of dwarf iris, about fifty yards from the slave -owners. Some five feet from the nest I notice a number of 30 TWO CHAPTERS ON ANTS. these ants congregated in the grass pulling away at an earth-worm. About two inches is unearthed, the remaining part is in the ground. Several ants are removing the earth from around the worm, while many others are holding on to it to prevent its crawling back. It is nine o'clock in the morning when I first observe them. At three in the after- noon a little more than four inches is un- earthed, and two inches or more of this is dead. There is considerable excitement around the nest; they are evidently mak- iug preparations for storing this huge mon- ster. A company are carrying a stick into the nest as thick as my little finger, and Over an inch in length; they soon return and take several smaller sticks, as if they were building a new apartment. It is now four o'clock, and their progress is so slow with the worm that I fear I shall not see the termination of the unearthing, so I take a small pair of forceps and assist the workers in pulling the worm out. There were about two inches remaining in the earth, and I found I had to exert a little strength in extracting it. This end is still alive and squirming. The worm is very large, full six inches in length. Much ex- citement now prevails among the workers ; SLAVE-MAKING ANTS. 31 they act very much like the slave- makers when they are capturing another tribe. In less than two minutes from the time I ex- tract the worm a large force of workers has come from the nest : not half the number can assist in carrying the worm at the same time, but they act as relays. About an equal number are at each end, fewer toward the middle. They all pull in the same direc- tion ; this makes a loop of the worm, and they must carry it through grass all the way. A large number are just in front try- ing to clear the road; grass is pulled down, small sticks taken out of the way. I lay a small stick three inches in length in their path; it is immediately removed by the force in front. But now they have become hopelessly entangled in the grass ; they can neither raise the worm nor pull it through ; at last they cut it in two ; about two inches of the dead part is taken oif and speedily carried to the nest by a part of the workers. The remaining portion of the worm con- tracts, so that it is not much more than three inches in length ; and now they move along rapidly, and soon have it housed. In less than live minutes after it is taken into the nest not an ant is to be seen ; the door is closed from the inside. This is the only 32 TWO CHAPTERS ON ANTS. species which I have observed that closes the entrance in this way. One other exploit of this colony, and I ANTS ATTACKING LARVA. will return to the slave -makers. I find a full-grown larva of Thyrens abbotii; it is nearly three inches in length, strong and robust, and, like nearly all of the sphinges, has a thick, tongh skin, and when it is dis- turbed is the worst -acting member of the family. I place it on the nest of this col- ony of ants, and they attack it in large numbers; they mount on its back and hang to its sides. The larva thrashes about and throws the ants right and left, but the plucky fellows are back again in an instant. The SLAVE-MAKING ANTS. 33 larva now tries flight on the smooth car- riage drive. This gives the ants the advan- tage ; they fasten their mandibles in every available spot. Again the larva stops and thrashes violently from side to side, and dis- lodges a good many, bnt not all. Again it starts at a rapid rate, most of the ants fol- lowing, bnt some turn back and go to the nest as if discouraged. The larva now comes to a little heap of d6bris washed here by the rain, and takes refuge under it. This sweeps all the ants off, and they seem puzzled for a moment ; but very soon they find where it is, and commence taking the light material from over it and throwing it to one side. Soon they reach it, and the larva, again feel- ing their mandibles, rushes out, and goes a few inches to another pile, where it again seeks refuge. By this time many of the ants have returned home, only about a doz- en remaining; but these soon unearth it; and now it goes very fast a little way, and brings up against a wall of brick set edge- wise in the earth to prevent the grass from encroaching on the drive. Instead of going over this wall — only an inch or so above the ground — it is trying to get its head under something. Only seven ants now remain ; but they are getting the advantage of the 34 TWO CHAPTERS ON ANTS. larva, and slowly worrying its life out. Ev- ery little while an ant comes across the drive from the nest, as if to see how his comrades are getting on, and usually stays and assists in trying to kill the game. By the time that it is nearly dead a largo force are on hand, and they drag it to the nest — some fifteen feet distant — more quickly than they did the earth-worm. On the morning of the 9th the red soldiers start in full force, and keep in line until they have gone about twenty yards. Here they disperse, and seem to be hunting over the ground ; but this proves a fruitless advent- ure, and they return home in line empty- handed. In an hour or so they again form a line and start in another direction, this time halting about thirty feet from the nest among some dry oak leaves. Here they at- tack a colony of yellow ants apparently as large and strong as themselves; but they prove to be great cowards, and skulk among the leaves, and flee in all directions. Prob- ably not more than a dozen are killed. The nest does not prove to be very rich in Iarva3 and pupse, for in about an hour it is plun- dered. Here, too, as in the case of the black ants, several adults are carried to the nest unhurt. The next day after the raid the SLAVE-MAKING ANTS. 35 yellow ants return to their ravaged home, and occasionally one comes near the nest of the red warriors, attracted by the sugar and honey with which I keep them supplied. It approaches very timidly even when its own species and the blacks are feeding alone, and runs away each time that an ant turns from the honey to go to the nest, as if afraid of pursuit. And I find that even tbe yellow ants will drive it away if they come in con- tact with it. But on two occasions I saw this yellow ant capture one of its own spe- cies that was feeding and domesticated with the reds, and carry it to its own nest. I think these two ants were nurses that had been so recently captured by the reds, and they were recognized by this yellow worker. The black and yellow ants never accom- pany their masters in their raids on other tribes, but stay at home and clear the pas- sages, open and close the entrances, and nurse the young. I tried many experiments to test the intelligence of the ants, which I must omit, as I wish to dwell more especially on the feature of their invasions. On the morning of the 18th the soldiers make a long march ; they go directly to a line fence, some thirty yards distant, which separates the grounds from a neighbor's 36 TWO CHAPTERS ON ANTS. garden. A board about six inches runs along the ground, to which pickets are attached. When the ants reach the fence, they all go through a small opening on the SLAVE-MAKING ANTS. ground, about three inches in width. The line has to converge here in order to go through, and sometimes considerable confu- sion seems to prevail, for more congregate than can pass through readily. It seems strange that they do not go between the pickets, for they are thickly scattered 011 the board just beneath. They soon pass out of my sight after going under the fence. In about three hours they begin to return with larvae and pupa). Evidently they are having a battle with the blacks (F.fusca), in which many are still engaged. Every little while a red warrior comes bringing a black and red soldier locked together. The black is dead, and the red crippled and un- able to free himself from his foe, and so they are taken together to the nest. This looks as if these red marauders were trying to take care of their wounded soldiers; for I have never seen them take a dead black ant to the nest except when it was locked to one of their own soldiers. This battle is simply a repetition of the one on the 1st of July. On the 23d of the month the red warriors attack a different species of black ant, larger and more robust than F.fusca. This* proves to be a very large colony. The nest is amou g 38 TWO CHAPTERS ON ANTS. the grass in the grove, about sixty feet from the iiest of the invaders. I was not aware of its existence, although I must have passed over it frequently. It is toward evening when the marauders come down upon this large, peaceful colony, and the inhabitants flee in every direction, not making the least exertion to defend themselves; the grass is fairly black with the fugitives. There are some ten or a doz- en openings in the space of a yard, through which they are pouring out. The red ants simply dance around the openings with ex- tended mandibles, scarcely even attacking the fugitives, yet seeming excited and im- patient to get to the nest, which is impossi- ble for them to do while so many are com- ing out. Finally they get possession of the nest, and commence transporting the pupa3 to their own dominions. I see no larvss, and most of the pupae are naked ; seldom is one enclosed in a cocoon. It is growing quite dusk, and still they work on, but the line is evidently thinning. At nine o'clock I take a light and find a very few engaged in work. At six in the morning I still find a few carrying pupa3, but by»eight o'clock the force is all out ; the line is from four to five inches in width, and SLAVE-MAKING ANTS. 39 extends from one nest to the other, about an equal number moving in each direction — the empty-handed coming toward the in- vaded nest, and those laden with plunder going to their own dominions. As soon as they deposit their spoils they resume the line of march. All day long this line is un- broken, at dusk it is considerably thinner, and by ten o'clock in the evening all have disappeared. During the entire day I saw no black ants around the nest, but every little while a ma- rauder would emerge with an adult black, which it carried to the nest ; and they capt- ured a large n umber of young ants that were still soft, and of a grayish color — not yet turned black. When I disturbed a cap- tor with one of these, it dropped it, and the young ant would try to hide under some- thing, and remain quiet until picked up by another warrior, when it would crouch and roll itself up in a ball, so that it could be carried just as easily as a larva or pupa. It reminded me of a cat carrying a kitten ; the young ant behaved very much like a kitten when carried. On the morning of the 25th a few of the marauders are around the invaded nest, go- ing in and out of the various openings, as if 40 TWO CHAPTERS ON ANTS. to make sure that nothing is left ; but they soon return to their own dominions empty- handed, and visit the ravaged nest no more. During the day I keep watch of the plun- dered nest, and occasionally a black ant comes timidly up and cautiously moves around; finally it ventures into one of the openings and disappears, but it soon comes out and walks away. Toward night of the same day a large number of the black fugi- tives return to their home, not in any reg- ular order, but from various points, and each is carrying a comrade which he takes into the nest. I can offer no solution of this; there was no battle, and these are not wounded soldiers. In most nests which I have observed there seem to be two sets of workers, one larger than the other ; the smaller seem to be the true nurses : it was these that were carried back to the nest. But why they did not re- turn in the same way they left is one of the mysteries of ant life. The returning fugitives all disappeared through the same opening, and. in the morn- ing this was closed, mostly with sticks and clumps of earth. I remove the covering, but not an ant appears ; it is fully an hour before they venture out, and now a dozen SLAVE-MAKING ANTSl 41 or more come out, and quickly reclose the entrance. A small place is left open, so that one at a time can squeeze in and out. I place sugar and various things about the nest, but they store nothing away, and eat sparingly. On the 3d of August I notice a very curi- ous proceeding on the part of these red -war- riors. Their nest extends into the edge of a tulip bed, which is bordered with the iris before mentioned. The bed is about three feet wide, and in the border just opposite is a nest of tiny yellow ants, with which I am unfamiliar, so small that they are scarcely distinguishable to the naked eye. They are scarcely longer than the little red ant which is often such a pest to house - keepers, but they are broader and more robust than this species, and of a light yellow color. From fifty to a hundred red marauders assail the nest of this tiny species ; but the openings are so small that they cannot get to the nest, except as they go to work and enlarge them, and this proceeding is fiercely resented by the little ants ; sometimes three or four will attack one of the invaders, fastening them- selves to him in such positions that he can- iiot reach them with his mandibles, and they hold on with such pertinacity that he finally 42 TWO CHAPTERS ON ANTS. becomes fairly frantic ; be doubles himself up and rolls about over the ground, trying to reach his tiny tormentors ; and now one of his comrades, attracted by his strange be- havior, stops and looks on, and walks around him, as if to learn what all this tumbling means. Seeming satisfied, he picks him up and carries him toward home. While he is being carried he is quiet. I take him away from his comrade and put him on the ground, when he again resumes his tumbling, until picked up by another and carried into the nest, as if the public highway was 110 place for such contortions. I put several of the red warriors, with this tiny species hanging to them, in alcohol ; the little things do not relax their hold, but die holding on to the big marauders. Sometimes an ant will continue work with one of the little things hanging to his antenna3,but more often they stop work and start for home when one is fastened where it cannot be reached : they are not carried home except when they roll about. The invaders work for several hours, greatly enlarging the openings, and at night return home with no spoils. On the fol- lowing day a few resume work, and keep steadily at it all day, and enlarge several SLAVE-MAKING ANTS. 43 openings, through which they can pass in and out readily. A rain-storm now comes on, lasting three days. During the storm the ants remain closely housed. On the morning of the 8th a dozen or more resume the work of exca- vation. By this time they have killed so many of the little ants that they can work without much interruption. What they are after is to me shrouded in mystery ; they certainly cannot want the larvse and pupre of such a tiny species as this ! On the 9th they still continue work, and on the morning of the 10th the treasure is unearthed, and proves to be a great num- ber of large winged females, longer than the red marauders, and with large full abdo- mens, so heavy that it takes two of the cap- tors to drag them to the nest. Many of the tiny workers have congregated about them, trying to defend them with their lives. But the great, helpless females allow themselves to be taken captive and dragged away with- out offering the least resistance. There must have been several hundred of these large females, and of course they had never seen the light. Probably the little workers would have released them before this if their home had not been assailed. 44 TWO CHAPTERS ON ANTS. I soon filled a small vial with the females which I took from the captors, and this was only a small proportion in comparison with what they carried to the nest. At the same time that these females are being taken captive a portion of the army are attacking another species of ant, about as long as themselves, but much more slen- der, and of a dark brown color. The nest is beneath a gravel -walk not more than ten feet from the nest of the assailants. As soon as they are aware of the danger which threatens them they come out in great num- bers, and the nurses have pupae in their mouths. This seems to puzzle the maraud- ers, and they allow most of them to escape ; but occasionally one tries to take a pupa from its nurse, but she will not give it up, so the cruel invader tries to take both nurse and pupa to his own dominions. But this proves a difficult proceeding, for she will not roll up and be carried peaceably, but struggles and holds on with her legs to va- rious things with which they come in con- tact. I turn monster and pick up one of these devoted little creatures, and handle her quite roughly, but she will not drop the pupa unless I pinch her quite smartly ; then she drops it in my hand, and bites fiercely, 46 TWO CHAPTERS ON ANTS. to which I patiently submit. When she has chastised me sufficiently, she picks up the pupa quietly, aud tries to make her escape. These ants move very gently, do not seem at all excited or hurried, and as soon as they reach the grass and clover they mount a blade of grass or stem of clover, and there they remain perfectly still, holding the pupa. The assailants pass beneath them, hunting over the ground, but not one, so for as I saw, was captured from a stem of clover or from a blade of grass, and sometimes a blade of grass would bend quite low with its burden. The assailants, satisfied that the game is gone, return to their own dominions. In about an hour from the time these ants were driven from home they begin to return, coming slowly down from the grass, where they have so patiently waited until the in- vaders were gone, and carry the pupa3 di- rectly back to the same opening from which they came out. The slave -maker (Formica sanguinea) is often confounded with the mound -builder (Formica n//a), good observers seeing no dif- ference in the appearance of the two species. But the habits of F. rufa are very unlike our slave -maker; the former are the greatest workers among our ants, and they keep no SLAVE-MAKING ANTS. 47 slaves. In the pine-barrens of New Jersey, which have never been disturbed by man, this species build large cities, often extend- ing over several acres. Scattered around a few feet apart, are mounds from two to three feet high and often from eight to ten feet in diameter, some of which may be centuries old ; the base is nearly as hard as stone, and covered with moss and lichens; radiating underground galleries lead from one to an- other, thus connecting all of the numerous mounds. An excellent observer, Mr. Henry Turner, of Cornell University, during his summer vacation made observations of F. rufa, bring- ing me his reports — as I did not like to leave the slave-makers long enough to make careful observations on these mound-build- ers; but I made short visits to their city, some two miles distant, to see them repair- ' ing damages done to their mounds, and 110 other species of ant ever assisted them in their repairs. These ants are fierce and aggressive, if simply disturbed during the working sea- sou, behaving very much like the slave- maker; they always succeeded in driving me from the field in a few moments. But I had the satisfaction of witnessing the Rev. 48 TWO CHAPTERS ON ANTS. Dr. M'Cook, with his assistants, make a raid on a portion of their city, which was done so promptly and energetically that the ants were completely nonplussed, not acting on the defensive at all. The centre of the mound was quickly cut through with a saw, and then with spades one-half was thrown aside, leaving the other standing, which showed the admirable arrangement of the various chambers and galleries leading to them. The mounds seem to be the nurseries where the helpless larvae are fed and nour- ished : immense numbers were exposed to view, which the ants .seized and carried to chambers below, concealing them from our sight ; so solicitous were they for the young that not one of our party was attacked, al- though we stood directly in their midst. On the 23d of July the last great raid was made by the slave-makers, but up to the 20th of August they went out iu detach- ments two or three hundred strong, despoil- ing the homes of the little yellow workers mentioned above. Sometimes two or three such detachments would start out in diifer- ent directions, each company keeping by itself and moving in line, precisely as the large army did earlier in the season. The SLAVE-MAKING ANTS. 49 tiny workers always fought bravely, trying to defend their homes. They would cling to the legs and antennae of the red warrior in such numbers as to entirely impede his progress. During the summer I occasionally saw a large ant, three-quarters of an inch in length, of a yellowish-brown color, with the excep- tion of a black head and tip of abdomen black. At last, on the 14th of August, I had the satisfaction of tracing one to its nest, which, to my surprise, was only about nine feet distant from the slave-makers7. The hole into which it disappeared was nearly an inch in diameter, and about two feet from the trunk of an oak-tree. There was nothing externally to indicate an ants' nest. I now place a leaf containing moist- ened sugar close to the opening. Soon an ant comes out and sips the fluid and re- turns; immediately four more come out and find the sugar. These must have been just within the entrance, and learned from their comrade of this rare treat outside. Soon eleven of these large ants are on the leaf. And now a red warrior, apparently wandering carelessly about, comes up and looks on, and at once starts toward home. He meets three comrades, touches each with 4 50 TWO CHAPTERS ON ANTS. his antennae, and they come directly to the leaf, look on a moment, and turn back as the first did. Quite a large detachment of sol- diers have j ust formed in line, and are march- ing past this nest at a point some five feet distant. As soon as the informers reach the line it causes a great disturbance, the column is broken, the soldiers seem confused, and rush about as if they did not know what to do. However, a large number soon find the leaf on which the ants are feeding, but they do not venture upon it — simply dance around with extended mandibles, as if daring them to come off. And now the large ants take alarm, and all save one make a simultane- ous rush, starting in different directions. Six are soon seized, each by three or four red warriors. Five of the struggling captives I release, and drop into alcohol. The sixth is disabled, and finally killed and left on the field. The remaining ant on the leaf behaves in a singular manner, as if not aware of the danger which surrounds her ; she has ceased feeding, and stands nearly perpendicular, passing her forelegs over her antennae and down the sides of her body. As soon as this work is completed she hur- ries away in an opposite direction from the nest, but is soon overtaken by the soldiers. SLAVE-MAKING ANTS. 51 I release her and place her at the entrance of the nest, and she disappears within. Why the ants did not make an effort to re- gain their home seems strange ; for the leaf was within three inches of the entrance, and most of the ants were not overpowered until they reached a point much farther away than the entrance of their home. Not one of the red warriors will venture within the nest, although no ants are visi- ble; yet they move around it excitedly, just as they did around the leaf. I take a gar- den trowel and cut away two or three inch-- es of the soil ; this does not damage the large cavity, and for a moment almost a solid mass of black heads rush to the front. This, then, is the secret of the timidity of the red soldiers. I push three into the lit- tle cavity I have just formed; again the black heads make their appearance, and seize two of the soldiers and literally chew them up, and again retreat out of sight. The soldiers by this time seem dishearten- ed, and the number is greatly decreasing ; soon they have all disappeared. As this large ant seems to be an unde- scribed species, I was very anxious to reach the nest in order to be able to give reliable information to the entomologist, who will 52 TWO CHAPTERS ON ANTS. point out its affinities and relationship to other groups, and give it a name and place in our fauna. So I cut the earth away with a trowel until I came to a hollow root, nearly circular, about an inch in diameter. There was nothing left but the outside shell or bark ; the earth surrounding it was clay, and quite hard, so I abandoned the task. In a few days afterward Mr. Turner took up the work of excavation, and followed the hollow root in a diagonal direction beneath the surface of the ground toward the trunk of the tree. He cut off sections of it, throw- ing out ants as he progressed — which were continually coming to the front to see what new danger was threatening their home — until he was brought to a stand by coming in 'contact with the oak, under or among the roots of which the nest must be situated, for the hollow root was simply a passage leading to it; but he could not proceed far- ther without injury to the tree ; so the earth was thrown back and pressed down, and the passage to the nest ruined. I now kept watch to see where the ants would next make their exit. I soon found they had a secret passage on the opposite side of the tree in a bed of moss which perfectly con- cealed the opening. SLAVE-MAKING ANTS. 53 As with most ants, there are two sets of workers among this species, one consider- ably larger than the other, and the smaller is larger than the slave-maker. It is the most quiet, unobtrusive species which I have ever observed. I have often met solitary individuals in the pine-barrens of New Jer- sey. They wander a long distance from the nest, always singly, and return in a direct line. I have followed one from the orchard, a distance of several hundred yards, direct to the nest, and it never seemed bewildered nor made any useless deviations in its course. After the 20th of August there is a marked change in the behavior of the slave-makers ; they no longer make predatory excursions, yet they are very active about the nest — not themselves doing any work, nor even feed- ing, but they seem to be bringing the differ- ent species which they have captured under more perfect subjection. The cowardly black ants mentioned in the preceding pages — the very large colony capt- ured and put to flight on the 23d of July — are now doing the principal work of excava- tion, while the brown and yellow ants are mostly the caterers and nurses of the com- munity. Around the nest are four large oak leaves, 54 TWO CHAPTERS OX ANTS. one holding moistened granulated sugar, an- other honey, and one with hard lumps, and the last with crumbling sugar. A large number of nurses crowd around the honey and moistened sugar, while others are en- gaged in carrying the lumps within the nest. That the ants comprehend difference in size is very apparent, and they are ambi- tious to secure the largest. I have often put a large piece in the path of an ant that was carrying a small one, and found that different individuals of the same species will often act unlike. One immediately drops the small piece she was carrying and tries to take the larger ; another will pause and go all round the big one, but still hold on to the small piece, and then hurry off to the nest and deposit it, and bring two or three companions to assist in securing the prize. And with the crumbling sugar one ant will attempt to carry a large lump ; and as she seizes it, she finds she has only a small particle in her mandibles. She throws it down, and tries again, with the same rssult ; sometimes she makes half a dozen or more such attempts before she succeeds in carry- ing off the large piece. Another ant will carefully carry each particle that comes off and deposit it within the storehouse ; and SLAVE-MAKING ANTS. 55 when it no longer crumbles, she carries the large piece. By the last of August there is a regular division of labor among this mixed colony, all brought about by the determined, perse- vering will of the slave-maker. There are now eleven openings to the nest, where the miners are at work ; and this mining, as far as I can see, is wholly carried on by the blacks. They seem to be preparing for win- ter, making excavations below the frost- line, and are now bringing to the surface a brick-red earth. This stratum of red earth varies in depth in different localities — from eighteen inches to three feet below the sur- face. Where this nest is situated it is just three feet below the surface. The slave-owners are constantly moving about, seeming to superintend everything — looking after the yellow nurses, and after the browns and yellows that are bringing in animal food. Quite a large number of various species of ants are attracted from other nests to the food which surrounds the home of the slave- maker, and very cautiously they steal up to the coveted honey and sugar; finding a va- cant place on the leaf, they quietly slip in to the feast. One of the masters is now 56 TWO CHAPTERS ON ANTS. making a round of inspection ; lie walks around the outside of the circle of feeding ants, touching each with his antennae as he proceeds, until he conies to a stranger, when he immediately seizes her, shakes her rough- ly, and lets her go. In no instance have I seen him kill one of these ants; he simply drives her away. The nurses do the same thing if they happen to come in contact with a stranger — even if she is one of their own species — but they do not make it their business to go round the circle and touch each ant as their masters do. If a black ant wanders away from the work of excavation, it is almost certain to be found and brought back by one of the numerous alert masters, who simply touch- es the slave with his antennae, when she crouches before him and rolls up. The mas- ter carries her to one of the entrances and disappears within, as if to discipline her. At all events, the slave soon comes out with a bib of earth in her mandibles, and now continues to work. This was repeated a great many times. I often marked the ants, so there could be no mistake about the one carried in soon coming out and keeping at work. Occasionally one of the masters would come out of an opening with a slave SLAVE-MAKING ANTS. 57 and cany it to another place where the mining was going on, as if more force was needed at that point, and the slave would continue to labor where she was put. The slaves act very differently from a colony of free ants of the same species. "A little more than fifty feet distant from the slave-makers is a large colony of blacks that were not disturbed through the summer. Here all kinds of work is being carried on at the same time. Some are hunting ani- mal food, others are sipping the juice from pears and grapes which lie near the nest, while a large number are partaking of the honey with which I keep them supplied, and others are clearing the passages and galleries of their home. The same is true of the brown ant in her own dominions, but as a slave she is simply a caterer and nurse. Early in the season, before the sla.ve-maker had so many blacks in the colony, the browns and yellows both helped to clear the passages and open and close the en- trances, and the masters would occasionally take hold and help close an entrance. It is thought by some excellent observers that ants do not hear ordinary sounds, but any careful observer must conclude that they are cognizant of sound made upon the 58 TWO CHAPTERS ON ANTS. ground. How it is communicated I do not know ; I can only see effects. A large num- ber of ants feeding together will rush off in the wildest confusion when a little unusual noise is made upon the ground. Two colo- nies— one brown, the other black — are lo- cated near the carriage drive. Often, espe- cially in the morning, the simple sound of the gravel under my feet as I walk past the feeding ants is sufficient to make them leave their food and run quickly within the nest. I suspend a leaf by means of fine thread six inches from the ground; it swings clear from everything ; I put honey upon it, and now take a thin piece of shingle and rest one end lightly against the edge of the leaf, while the other end rests upon the ground. Soon the ants find the honey, and crowd upon the leaf. I remove the shingle, leav- ing them no direct communication with the ground. I pick up the ottoman upon which I was sitting, and let it drop a little heavily some two feet distant from the ants; they rush from the leaf headlong in every direc- tion. But I can raise quite a din above them, even striking tin and various other things, and they seem to pay no attention if the noise is a foot or so above them ; and sometimes when it is not more than six SLAVE-MAKING ANTS. 59 inches from them they do not heed it; at other times they take alarm, which seems to be communicated by one or two apprising the rest of the unusual proceeding, which I think is seen rather than heard. But our warlike slave-makers will not run for anything ; they are always ready for a fight ; any unusual noise only seems to ex- cite them. I kill eight slave-makers, and place them near one of the entrances. Their comrades soon throng around them, acting excitedly, hurriedly touching each other's antenna?, now moving in circles around the nest as if to find the author of the mischief. Finding nothing unusual, they become quiet, and again direct their attention to their dead comrades. Three are found to be not quite dead; their legs move. These are carried within the nest, the others are taken a long distance off and left. Very soon a black slave brings one of the dying masters out of the nest, and drops him within a foot of the entrance. He hap- pens to rest against a little pebble in such a position that he is nearly upright, and is so nearly dead that he stays just as he was left. One of the nurses, going to the nest laden with honey, sees him and stops; she raises 60 TWO CHAPTERS ON ANTS. herself up until her mouth reaches her dying master's, and tries to feed him ; finding no response, she leaves him and continues on her way. Two other nurses make the same attempt, the position in which the ant was placed doubtless attracting their attention. As far as I have observed, when one ant feeds another they both stand nearly per- pendicular. When all is quiet about the nest I again repeat the experiment, killing a number of soldiers. I pick them up here and there, and kill them quickly, until I have twen- ty dead in my hand. I now pour them all down near one of the leading entrances. Soon the wildest confusion prevails. The soldiers come out in such numbers that I retreat a few steps. The slaves, aware that something unusual is going on, have stopped work and disappeared — all save one, which is busily engaged in carrying sticks and other things to close an entrance about a foot distant from where I dropped the dead soldiers. The circle widens, and many of the angry soldiers rush up excitedly to the black slave. Seeming satisfied that she is not the author of this terrible havoc, they leave her, and she continues her work with the utmost indifference to the excitement SLAVE-MAKING ANTS. 61 around her. At last one of the warriors, not as keen-sighted as his comrades, seizes the poor slave with a death-grip ; two or three others, attracted by the struggle, also seize her, and soon tear her in pieces. This is the only time I ever saw the soldiers kill one of their own slaves. After the excite- ment dies away, the soldiers treat their dead companions as in the first instance, carry- ing some away, and others which move are taken within the nest. I now take a handful of small sticks, from half an inch to an inch in length, and pour them down, which nearly closes the main entrance. This makes quite a commotion for a few moments among the soldiers, but nothing like the agitation caused by their dead comrades. The slaves soon remove the sticks, while their masters assume the defensive, and bluster around, doing noth- ing. But the most remarkable and amusing feature in the behavior of these slave-mak- ers is the solicitude with which they guard the food that is placed around the nest — • the more remarkable that they seldom touch the food themselves. Wasps, honey-bees, bumblebees, two -winged flies, are all at- tracted to the honey aud sugar, but they 62 TWO CHAPTERS ON ANTS. are not allowed to remain at the feast. The ants are not obliged to touch these insects to enable them to ascertain whether they are members of the colony, but they see from afar, and usually three or four will simultaneously attack a bee, grasping it by the legs ; the bee struggles, trying to free herself from her persecutors, but not until she rises to fly will they let go their grasp. Among these insects is one cunning hum- blebee that has in a measure learned to evade the attacks of the warriors. She is very quick to see in every direction around her, and if only two or three attack her, she stands on three legs, holding the others up beyond their reach. In a week both mas- ters and slaves have become so accustomed to this persistent bumblebee that they sel- dom attack her, yet still drive off all other insects the moment they alight upon the leaf. But the bumblebee is still cautious and wary, and elevates her feet on the side that an ant approaches. After awhile she adopts another stratagem. AVhen one is coming toward her she faces about and strikes quick and repeated blows with one of her forelegs ; if the ant persists in com- ing, it receives the blows, and usually re- treats. She never disturbs the ants except SLAVE-MAKING ANTS. 63 when they attack her ; all she asks is to be let alone. It will be remembered that in the preced- ing pages a slender brown ant was mention- ed, which, when assailed by the slave-maker, behaved very differently from all other spe- cies ; coming out of the nest with pupae in their mandibles, they mounted blades of grass and stems of clover, where they re- mained holding the young until the danger was over. Some of these ants with the pupae were captured. In a week or so af- ter, I noticed a few were domiciled with the slave-makers, and seemed to be contented with their surroundings; but their habits were so unlike the other species in the col- ony that they were of no use whatever, and proved to be a great trouble and annoyance to their masters. One of their habits is to cover all the food they cannot carry into the nest ; so, when they found the honey, two or three of these ants set to work to conceal the treasure. They first brought small pebbles and large grains of sand and placed them around the outer edge, making a little wall ; then they brought bits of sticks and leaves, and pieces of green moss, and threw them over the wall on to the honey. The masters, in mak- 64 TWO CHAPTERS ON ANTS. ing their investigations, notice this unusual accumulation of material over the food, and often pick up the largest pieces and throw them off the leaf. While one is thus en- gaged in clearing the leaf, a little irrepress- ible brown captive is making her way to the honey with a piece of green moss, about an inch in length, which she has cut off with her strong mandibles. The outer edge of the leaf which holds the honey is an inch or more above the ground, making it quite difficult for her to reach it with her burden. But at last it is accomplished, and just as she is about to put it in place the inspector who is undoing her work tries to take it from her ; she holds on, will not give it up ; he now lets go, and takes hold in another place, but cannot wrest it from her ; again he drops it, and now picks her up and car- ries her to the edge of the leaf and drops her on the ground among the rejected ma- terial, but she still clings to the moss. She seems bewildered for a moment, but soon finds her old track, and again ascends the leaf. This time she does not encounter the inspector, and deposits the moss. This proceeding on the part of the slen- der brown ant and the slave -maker was continued for nearly a week, and then the SLAVE-MAKING ANTS. 65 browns disappeared. Whether they were driven away, or finally left of their own ac- cord, I am unable to tell. I found the ants were quite fastidious with regard to the kinds of larvae and in- sects which composed a large share of their diet, wholly rejecting some, and very eager to secure others. The oak worm (Dryocampa senatoria) was refused in all stages of its growth, but the chrysalids and moths of this species were both taken within the nest. Another larva (Eudamus titryus), which feeds OR the locust, I supposed would be a rare treat to the ants, as it has a soft, smooth, fat body, and is very quiet during the day, hid away between locust leaves which it has sewn together with silken threads of its own manufacturing ; but in this I was mis- taken ; all species of ants turned away from it, apparently in great disgust. But the larva of the common yellow butterfly (Colias philodice)j which feeds on clover, was greed- ily sought for, and large numbers taken to the nest. Also the Iarva3 of some geometer which I did not recognize were taken from the trees, the ants often ascending twenty feet or more along the trunk of a tree, and then running out on the branches to the leaves where they secured the prey, and de- 5 66 TWO CHAPTERS OX ANTS. sceuded with it safely, although frequently it was much larger than the ant which car- ried it. But there was nothing for which the ants seemed more eager than for the corn worm (Heliothis armigwa), which feeds upon the tender kernels of green corn. I sometimes took several of these worms to a nest of ants, and very seldom would one escape, al- though it fought valiantly, and seemed too intelligent to deserve such a fate. With its strong jaws it would pick off the ants that were clinging to its body, and throw them right and left, sending them two or three inches away. But lack of strength was made up by perseverance and numbers, so the ants were usually victorious ; even when the worm succeeded in getting twenty feet away from the nest, it was overpowered and brought back. All the insects which I have observed, however alert and strong, are afraid of the ants, seeming at once to recognize their power and dominion. A large carnivorous beetle (Calasoma scrutator} happens to come near a company of ants which are engaged in killing a corn worm ; it stops and looks on. I fully expected to see it pounce upon the worm, and attempt to take it away ; but SLAVE-MAKING ANTS. 67 no; several ants start toward the beetle, which sees them,, and evidently thinking discretion the better part of valor, it runs away. I carried several slave-makers to a colony of brown ants, many of which were crowd- ed around the honey, and dropped them among the feeding ants. A battle ensued. Superiority of strength, however, was final- ly overcome by multitudes ; as fast as a brown ant was disabled it was replaced by a fresh one, so that not a single red es- caped ; but more browns were killed in the conflict than reds. After the slave-makers were all killed, it was amusing to see the difference of mind manifested with regard to the disposal of the enemy. Some of the ants were determined to take the mutilated remains within the nest, while others were equally bent on carrying tnern a long dis- tance away. Two ants of opposite mind seize the body of the enemy and struggle over it, now one gaining a few inches of ground, then the other, until a third comes up and settles the difficulty by deciding in favor of its being carried away ; so the one ant is obliged to yield to the two, and gives up the contest and remains at home. The two ants work together a short time, and 68 TWO CHAPTERS ON ANTS. then one returns to the nest, while the other proceeds with the remains until she reach- es the distance of some thirty yards, and leaves it on the carriage drive. Their own wounded were all taken within the nest, and a part of the dead were taken in ; but the next day I saw three dead brown ants brought out and carried away. Through the summer this colony of brown ants were all nearly of one size, and I sup- posed there were no minor workers among them ; but on the last day of August I saw a large brood around the entrance of the nest not more than half the size of the rest of the colony, and they were teasing the nurses to stop and feed them, precisely as I had seen the slave-makers doing a month earlier. Some of the nurses would heed their entreaties, another would turn back and go toward the honey, followed by two or three of these inexperienced young. On reaching the food the nurse would put her mouth down to it, as if showing these young ants how to help themselves (she certainly could want no more herself; her honey-sac was rounded out almost to bursting), which they usually did, at first making awkward work, very much like a young kitten in its first attempts to take milk from a dish. SLAVE* MAKING ANTS. 69 But in a day or two all of these ants helped themselves as neatly as their elder sisters, and now did their share of work ; in fact, they seemed more active than the worker major. All through September and up to the mid- dle of October the mining-work was carried on at the home of the slave-maker, as far as I could see, entirely by the blacks. On chilly days no reds were to be seen, but the nurses and miners still continued to work • and free colonies of blacks and browns were also actively engaged. By the last of October the war spirit of the slave-maker has greatly decreased, and insects of all kinds are allowed to come about the nest to regale themselves on the fruit and sugar. Only on the warmest days do the masters attempt to drive them away ; but the slaves still continue to attack these various insects when they come in contact with them. I do not pretend to know what the pri- mary object is of the raids made by this red ant on other tribes, but whatever the object, the result is a large number of slaves in subjection to their masters. The red ant is not as large as some spe- cies it enslaves ; but on comparing the shape 70 TWO CHAPTERS OX ANTS. of the liead and tlie mandibles of the vari- ous species, we find our slave-maker has a broader head and more powerful mandibles than the enslaved ants, also a stronger coat of mail than the other species. The ants were held under the microscope by means of stage forceps, which closed on them with a steel spring. This instrument almost invariably killed the slaves, while the masters stood the ordeal apparently un- hurt. On releasing one and taking him back to the nest, I have often seen him at- tack and whip a stranger as quickly as be- fore he was subjected to the experiment. Even while at peace he always walks about with extended mandibles, which gives him a fierce look, while the other species keep theirs closed except when actively en- gaged. No doubt all of the wingless ants are un- developed females, and, strictly speaking, the feminine pronoun should be used; but as power and strength and the war spirit are essentially masculine elements, I have preferred to speak of our slave-maker in the gender in which these qualities are sup- posed to reside. I submitted the various species of ants mentioned in the articles to Mr. Cressou, SLAVE-MAKING AXTS. 71 who handed them over to the Rev. Dr. M'Cook, who is interested in this family. Dr. M'Oook gave me much valuable help, but modestly disclaims ability to classify and name. He says : "My own studies have been greatly in your line, viz., the life habits. I have been driven to give some attention to classifica- tion by the same embarrassment which you now feel. I found it impossible (in Amer- ica) to get names.7' So the ants were named by Dr. Auguste Forel, of Munich, Germany, as follows : "The slave -maker — Formica sail guinea, Latr. var. — F. sanguined amcricana. "The black slave — Formica fusca, Lim. "The brown slave — nurses of the com- munity— Formica schanfussii, Mayr. " The yellow slave — also nurses — F. sclian- fttssii, var./owcee. "The small yellow ant, clinging to the legs of the slave -maker — Lasius Jiavus, De Geer, American var. " The large ant, with black head — Campo wot us meleus, Say. " The slender brown ant, which could not be made a tractable slave, is a new species, and named by Dr. FoTQlApJiaenogaster Treati." I ara also indebted to Mr. S. H. Scudder 72 TWO CHAPTERS ON ANTS. for assistance. And I specially wish to ac- knowledge the kindness of iny friends Rev. Mr. Pittenger and Rev. Mr. Harrison, the former for help in anatomical investigations, and the latter for ascertaining the depth of the red strata of earth in which the ants were mining. II. THE HARVESTING-ANTS OF FLORIDA. IN the low pine -barrens of Florida are large districts thickly dotted over with small mounds made by a species of ant whose habits are unknown to the scientific world. Each mound is surrounded by a circle of small chips and pieces of charcoal, which the busy inhabitants often bring from a long distance. The hills are regular in outline, with a crater-like depression on the summit, in the centre of which is the gate- way or entrance. These ants do not live in vast communi- ties like the mound-builders of the North, but each hill seems to be a republic by it- self, though separate colonies in the same neighborhood have friendly relations with 74 TWO CHAPTERS OX AXTS. each other. Their color is rufous or red- dish-brown, ami they are furnished with stings like bees and wasps, and, like the honey-bee, always die after inflicting a wound, for their stings are torn from their bodies and left in the victim. The pain in- flicted is about the same as that caused by the sting of the honey-bee. But they are not as vicious as most stinging insects: they will submit to considerable rough treatment before resorting to this last resource. There are three sets of neuters in each colony — major and minor workers and sol- diers $ also one wingless queen is found in each nest. The head is very large, espe- cially that of the soldier.* The workers minor — which are the true workers — have regular, well-defined teeth on the mandi- bles, while most of the soldiers have merely the rudiments or teeth entirely obsolete. All the queens which I have found — eighteen in number — have perfectly smooth mandi- bles, without the least vestige of a tooth. Early in December, 1877, 1 brought a large colony of these ants from one of the hills, * I use the term "soldier " for the sake of definite- ness. The soldier approaches the queen in size, and in mauy of the specimens the head is larger than that of the queen. THE HARVESTING ANTS OF FLORIDA. 75 including tlie workers major and minor and soldiers, and established them iii a glass jar which I placed in my study. They very soon commenced work, tunnelling the earth and erecting a formicary, as nearly as they could after the pattern of their home on the barrens. The mining was done entirely by the small workers. At first they refused all animal food, but ate greedily fruit and sug- ar ; and all kinds of seeds which I gave them were immediately taken below, out of sight. I now visited the mounds on the barrens, and found abundant indications of their food-supplies. At the base of each mound was a heap of chaff and shells of various kinds of seeds. The chaff was Aristida speci- formis, which grew plentifully all about. I also found many seeds of EnphorUa and Cro- ton, and several species of leguminous seeds. But the ants were not bringing seeds in at this time of year: they were only carrying out the discarded seeds and chaff; and only on the warmest days were they very active. But they do not wholly hibernate. Even after a frosty night, by ten o'clock in the morning many of the hills would be quite active. I sent specimens to the Rev. Dr. M'Cook, of Philadelphia, to be named, and he iden- 76 TWO CHAPTERS ON ANTS. tified them as Pogono myrmex crudeUs, de- scribed by Smith as Atta crudelis* Dr. M'Cook predicted, from their close structu- * " Hymenoptera of the British Museum :" Formi- cidsea, p. 170. THE HARVESTING-ANTS OF FLORIDA. 77 ral resemblance to the Texan "agricultural ant," that they would prove to be harvest- ing-ants. On excavating a nest, I found chambers, or store-rooms, filled with, various kinds of seeds. But, so far as I have observed, the seeds are not eaten until they are swollen or sprouted, when the outer covering bursts of itself. At this stage the starch, is being converted into sugar, and this seems to be what the ants are after. They also seemed to be very fond of the yellow pollen-dust of the pine. The catkins of the long -leaved pine (Pinus australia) commenced falling in February, and I noticed ants congregated on them ; so I took those j ust ready to dis- charge the pollen, and shook the dust on the mound in little heaps, which were soon sur- rounded by ants, crowding and jostling each other in their eagerness to obtain a share. The colony in the glass jar seemed per- fectly contented, not trying to make their escape at all. The earth was originally a little more than, two inches in depth, but by the first of February these wonderful archi- tects had reared their domicile to the height of six inches. They raised tier upon tier of chambers in so substantial a manner that they never fell in. One of the store-rooms 78 TWO CHAPTERS ON ANTS. ill which they deposited the seeds I gave them was at the bottom of the jar, and the seeds were stored against the glass with no intervening earth between : it contained about a teaspoonful of millet. I gave this chamber the right degree of beat and moist- ure to sprout tbe seed by pouring a little water down the side of tbe jar until it pen- etrated the chamber, and then setting it near the fire. Tbe ants soon appreciated the condition of this store-room, and many congregated tbere and seemed to be enjoy- ing a feast. The next day the seeds were all brought to tbe surface and deposited in a little heap on one side of the jar, where many of them grew, making a pretty little green forest, which tbe ants soon cut down and destroyed. This chamber remained empty for three or four days, and was then again refilled with fresh millet and apple and croton seeds. I kept a small shell, which held about a table-spoonful of water, standing in the jar for the ants to drink from. For more than a month the water was allowed to remain clear, the ants often coming to the edge to drink; but one day one was walking on the edge of the shell, and carrying an apple- seed, when she lost her footing and rolled THE HARVESTING-ANTS OF FLORIDA. 79 into the water. She floundered about for a few moments, still holding on to the seed : at last she let it drop and crawled out. As soon as she had divested herself of the sur- plus water, she consulted several of her com- panions, and they immediately went to work and filled up the shell, first throwing in four or five apple-seeds, and then filling in with earth ; and ever after, as often as I cleared out the shell and put in fresh water, it would be filled with earth, sticks, and seeds; and they now served all sweet liquids which I gave them » in the same way, sipping the sirup from the moistened earth. Like other ants, they are very fastidious about removing their dead companions. I buried one about half an inch beneath the soil. Very soon several congregated about the spot and commenced digging with their forefeet, after the manner of digger-wasps, throwing the earth backward. They soon unearthed and pulled the body out, when one seized and tried to remove it, climbing up the side of the jar, and falling back until I relieved her of the burden. From time to time I add new recruits of soldiers and workers to the jar. This al- ways causes a little confusion for a few mo- ments : there is a quick challenging with 80 TWO CHAPTERS ON ANTS. antennae, but no fighting, and soon all are working harmoniously together. I found three half -drowned, chilled ants near the mound from which most of the inhabitants of the jar were taken. One was not only wet and chilled, but also covered with sand. These I put 011 a small leaf and placed in the centre of the jar. The genial warmth soon revived them. Many of their old com- panions clustered arouud them, aud there seemed to be considerable consultation. The two wet ants were soon made welcome, and, leaving the leaf, were conducted by their comrades — from whom they had been sep- arated for more than two mouths — to the rooms below. But the one covered with sand — a major — did not meet with so kind- ly a reception. She still remained on the leaf trying to cleanse herself. All the ants had leffc her save one, who was determined to quarrel with her. I removed this one, and now another came up, bit at her and annoyed her until I removed this one also. Then some half dozen congregated about the leaf, touching her with, their antennas and walking round her. By this time she was nearly free from the sand, and was look- ing quite bright, strutting about the leaf in a threatening attitude, with her mandibles THE HARVESTIXG-ANTS OF FLORIDA. 81 wide apart. She was not attacked by these last inspectors, though still looked upon, a 1. WORKER MAJOR: 2. OUTLINE OF HEAD OF WORKER MAJOR ; 3. OUTLINE OF BODY OF WORKER MINOR. 6 82 TWO CHAPTERS ON ANTS. little suspiciously. I then returned the two quarrelsome ants : they immediately walked up to their unfortunate comrade, and now seemed to be satisfied that she was a re- spectable ant, and admitted her into the community with no further challenging. I found a nest of large carpenter-ants (Camponotus atriceps, var. esuriens, Smith) which had made their home in fallen tim- ber. Upon examining their work, it was evident they must have strong tools to work writh, for the numerous rooms and chambers of their domicile were often made in firm, hard wood. They are the largest, most vi- cious species I have ever seen. I introduced one of these terrible creatures into the jar among the quiet, peaceful occupants. A large worker major immediately closed with her : it was so quickly done that I could not tell which was the attacking party. They rolled about a few moments in a close em- brace, till they rolled out of sight through the wide entrance to one of the rooms be- low. There was considerable excitement and increased activity among the workers, who were constantly bringing to the surface bits of earth which the struggling warriors had loosened. In about an hour the head of the carpenter was brought out, divested THE HARVESTING- ANTS OF FLORIDA. 83 of every member: both the antenna? and palpi were gone, cut close to the head. A little later the abdomen was brought out, and still later the thorax, with not an entire leg left. QUEEN : SIDE VIEW, SHOWING PECULIAR CONFORMATION OF THE T1IOKAX. Several times during the months of Jan- uary and February I introduced into the jar a number of half -grown larvae of the harvester. Without any hesitation they were quickly carried to the rooms below by the workers minor. On the 4th of Febru- ary I found a large number of the larvae of the carpenter-ant (Camponotus meleus, Say). They were very small, and closely packed together in a chamber cut out of hard wood, two inches in length and an inch and a quarter in diameter, nearly circular. It was packed full of larvae and eggs, the Iarva3 ap- parently just hatched. I detached a small 84 TWO CHAPTERS OX ANTS. mass, all stuck together, and placed them in the jar with the harvesters. The workers minor immediately surrounded the mass, touching it with their antenna, and then retreated backward, passing their forelegs over the head and antennae, as if the larvae were obnoxious to them. Great commotion ensued, followed by an apparent consulta- tion lasting a few moments; but soon the usual quietness reigned, and most of the ants left the helpless larvae and returned to their mining and to the storing away of seeds or feeding their own young. But two or three had not entirely deserted the young carpenters. Again and again they touched them, and then retreated, cleansing the an- tennae as they moved backward. At last one seized the mass and held it in her man- dibles, standing nearly in an upright posi- tion. Several workers now surrounded her, picked the larvae off, one by one, and carried them below, until all were separated and disposed of. But by far the most satisfactory way of studying the ants is in their native haunts on the barrens, where I had ten nests under observation. One of these was so situated that it received the direct, rays of the sun all day, and was protected from north and THE IIARVESTISG-ANTS OF FLORIDA. 85 east winds by dense, low shrubbery. On sunny days, even with a cool wind from the north, when taking my seat in this shelter- ed spot, I would soon become uncomfortably warm. This hill was always active when- ever I visited it, while in other localities the ants would often be all housed. Around this active nest I stuck stems of millet eigh- teen inches high, surmounted by the close- packed heads. The ants climbed the stems, loosened and secured the seeds, and stored them within the nest. They worked vigor- ously, sometimes twenty or more on one head pulling away at the seeds. In my ar- tificial formicary they did not mount the stems, even when the heads were not more than three or four inches from the ground, but seeds that I scattered in the jar were always taken below. I threw down a handful of apple -seeds near the entrance of the active hill on the barrens. This immediately attracted a large number of excited ants. They rushed to the seeds in a warlike attitude, and began carrying them off, depositing them two or three feet away. But as soon as the excite- ment caused by the sudden pouring down of the seeds had subsided, they seemed to comprehend that they had been throwing 86 TWO CHAPTERS ON ANTS. away good seeds ; and now, changing their tactics, not only carried the remainder into the nest, but finally brought back and stored all those that had been thrown away. On excavating the nests we found grana- ries of seed scattered irregularly throughout to the depth of twenty-two inches below the surface of the ground : some were near the surface, and a few sprouted seeds were scat- tered about in the mound. The mound is usually not more than four to six inches above the level of the ground. The great majority of nests that I have found are in the low pine barrens — so low that on reaching the depth of two feet the water runs into the cavity like a spring, and stands above some of the granaries. Not- withstanding this wet locality, I found 110 sprouted seeds in the deeper store-rooms, but only in the warmer mound. On sun- ny days the larvae are brought up into the mound and deposited in chambers near the surface, where they receive the benefit of the sun's rays. On cool, cloudy days and in the early morning I found no larvae near the surface. If the ants are intelligent enough to treat the larvae in this way, why should they not store seeds where they will not sprout? And when they need to sprout THE HARVESTING-ANTS OF FLORIDA. 87 them in order to obtain the sugar they con- tain, it would take no more wisdom to treat the seed as they do the larva) — bringing them near the surface to obtain the right degree of heat for the required result. The little workers seem very determined not to allow any green thing to grow on their mounds. Cassia and croton and many other plants start to grow from seeds which the ants have dropped, but they are always cut down and destroyed if too near the mound, though allowed to grow at a little distance ; so that a botanist would be as- tonished at the great variety of plants with- in a small area if not aware of the source from which they came. I sometimes found small shrubs of Kalmla hirsuta and Hyperi- cums entirely dead on the mounds, the roots completely girdled in many places. It is very amusing to watch them in their efforts to destroy grass and other plants. Their determined persistence is remarkable : they cut off the tender blades and throw them away. But they do not stop here : the roots must be exterminated; so several dig around the plant, throwing the earth backward, and after making it bare they cut and girdle tho roots until the plant is killed. Early in March the ants in the jar seemed TWO CHAPTERS ON ANTS. to have completed their domicile. At first, several chambers were visible through the 11 - formed teeth. 2. Partially developed. 3. Entirely obsolete. MANDIBLES OP TIIE HARVESTING-ANT. glass, and the galleries leading to them, but gradually the light was all shut out by plac- ing little particles of earth against the glass, thus depriving me of the opportunity of watching their movements within the nest. So I now took the jar to the barrens, and set it by the side of a nest which was about a mile distant from where most of the ants were obtained. Here I carefully broke it, and took the thin shell of glass from around the nest, which did not fall, but stood six inches in height and eighteen inches in cir- cumference. With a large knife I removed a thin layer of earth, which revealed three admirable chambers, with galleries leading THE HARVESTING-ANTS OF FLORIDA. 89 from one to the other. Immediately below there were five chambers well filled with ants, and below these other chambers were scattered irregularly throughout, with only thin partitions between. At various times I had given the ants moistened sugar on the thick curved leaves of the live-oak, and several of these had been covered while the ants were making their excavations. Two of the leaves were three inches below the surface, and the ants had utilized them by making the inner curved surface answer for the floor and sides of fine chambers ; and here a large number of ants, both soldiers and workers, were crowded together. In other chambers I found the larva?, which were greatly increased in size since I had placed them in the jar; and the larvae of the carpenter-ant were being reared, as I found some smaller than any I had in- troduced belonging to the harvester. Very soon a great crowd of excited ants canie from the hill near which I had broken the jar, and began to transport the larva?, and also the mature ants, to their own do- minions. There was no fighting: the ants from the jar submitted to being carried, not offering the least resistance. A small work- er would often take hold of a large soldier, 90 TWO CHAPTERS ON ANTS. sometimes pushing, sometimes dragging, her through the sand, and she would be as quiet as if dead or dying ; but if we touch the lit- tle worker, she leaves her burden and rushes about to see what the interference means ; and now the soldier straightens up, as bright and lively as the rest, and after passing her forelegs over her head and body, goes of her own accord into the new nest, meeting with no opposition. Some of the ants would coil up and allow themselves to be carried easily. Others were led along by an antenna or a leg, in either case manifesting no resistance. For three hours I watched the proceeding, and could see no fighting. It looked pre- cisely as if the inhabitants of the jar real- ized their helpless condition, and gladly sub- mitted to be taken prisoners, or to become partners with this new firm. I left them, and after the lapse of two hours again visited the spot. The seeds that had been in the jar were now being transferred to the other nest, and two new entrances at the base of the mound were being made. And now every little while an ant would be ejected from the nest. Oue wrorker would bring another out and lay her down, often not more than three inches away from the door, but, so far as I could see, she THE HARVESTING-ANTS OF FLORIDA. 91 was in nowise injured. Her first movement was to make herself presentable by pass- ing her forelegs over her head and body: as soon as this was completed she returned within the nest. But there was one large soldier which the whole community seemed combined against. She was led or dragged away from the entrance of the nest eight times, and each time left at the base of the mound among the rubbish. Sometimes she was led or carried by one alone, sometimes two or three would conduct her, and then leave her, when she would at once proceed to make her toilet ; which completed, she would again return to the door of the nest, when she would be again conducted away, offering no resistance. I now picked her up, which made her very fierce. She seized my glove with her powerful mandibles, and held on with a persistency equal to the most vi- cious species, at the same time trying to use her sting. As soon as I could free her from the glove I secured her, and on reaching home placed her under the microscope, and found she was not injured, and had strong teeth in her mandibles. Ou the next day I returned her to tho nest, and again she was met by the indig- nant police at the door and conducted awayt 92 TWO CHAPTERS ON AXTS. With her strong mandibles she could have crushed any number of her small assailants ; but in. no instance did she show the least disposition to rebel against the indignities to Avhich she was subjected. She was often dragged away, with her back 011 the ground and her legs coiled up, apparently helpless. If all the soldiers had been treated in this way, it would not have been so remarkable ; but so far as I could see the rest were allow- ed to remain, going in and out of the nest as if taking a survey of their new surroundings. For rive months I had these ants under almost constant observation, and yet I was unable to make ont the true position of the soldiers in the colony. They stay mostly within the nest. On the warmest days a few will come out and walk leisurely around the mound. They are not scattered irregu- larly through the nest, but seem to be housed together in large chambers. In one of these chambers I found a wingless queen in their midst. It seemed very fitting for a queen to be surrounded by Amazon soldiers ; but, alas ! they seemed more like maids of honor than soldiers, for they forsook the royal lady without making an effort to defend her. Not so, however, with the little workers; they rallied around her, ready to guard her THE HARVESTING-ANTS OF FLORIDA. 93 with their lives, and no doubt would have succeeded had it been any ordinary foe. This phenomenon — the soldiers and queens with smooth mandibles — is very puzzling, and has excited much interest among natu- ralists both in this country and in Europe. I sent specimens to Mr. Charles Darwin, which he forwarded to Mr. Frederick Smith of the British Museum (who, Mr. Darwin in- forms me, is the highest authority in Europe on ants and other Hymenoptera). Mr. Smith says : " Your observations on the structural differences in the mandibles of this ant are quite new to me." I also sent specimens to the eminent naturalist, Dr. Auguste Forel of Munich, who, like Mr. Smith, had never ob- served this feature of the mandibles in any ant ; but he has a theory to account for it — that the smooth mandibles have been worn down by labor. If this theory is true, how can we account for the fact that other ants do not wear down their teeth ? The chiti- nous covering of this harvesting-ant is firm and hard. The stage forceps of my micro- scope closes with a spring ; and in studying this ant I have put thousands of individuals to the test, holding them in the forceps to examine their mandibles ; and in no instance do I recollect seeing one injured, while many 94 TWO CHAPTERS OX ANTS. other species are easily injured by the for- ceps. Among these are the two large spe- cies of carpenter-ant before mentioned, which work in stumps or Mien timber. These ants all have well-developed teeth, and the shell- like covering enveloping the body is much thinner than that of the harvesting-ant. If it be urged that hard wood will not wear down the teeth like mining in the sandy soil, I can bring forward another member of this family (Camponotus socius, Roger), which lives in the ground, and whose mining and tunnelling are on a much more extensive scale than those of the harvesting- ant. The formicary of this Camponotus often extends over several square rods, with large entrances at various points, all connected by underground galleries, requiring a great amount of labor to construct them; while each colony of the harvesting-ant has a close compact nest or formicary, requiring much less work to construct it. The worker ma- jor of Camponotus socius is very large — larger than the soldier of the harvesting-ant. The formicaries of the two species are often in close contact, so that the nature of the soil is precisely the same. I have examined thousands of Camponotus socius, and in no instance have I found the teeth worn down. THE HARVESTIXG-ANTS OF FLORIDA. 95 There is still another difficulty in the way of Dr. Forel's theory. Careful observations have revealed the fact that all the harvest- ing-ants that engage in work of any kind are armed with teeth. I took thirty soldiers with smooth mandibles, put them in a glass jar with, every facility for making a nest, but they refused to work, scorned all my of- fers of food, and remained huddled together for three days. I then introduced several workers minor, and they immediately com- menced tunnelling the earth and making chambers, into which the lazy soldiers crawl- ed, meeting with no opposition from these industrious little creatures. My experiments did not stop here. I now took about a hun- dred specimens — soldiers and a few workers major, the last with partially-developed teeth — and placed them in ajar. Some of these made feeble attempts to construct a nest, but they did not store away seeds, and lar- vae which I put in the jar they carried about as if not knowing what to do with them. There is every appearance of an aristoc- racy among these humble creatures. The minors are the servants who do the work, while the queens and soldiers (especially the soldiers, which more nearly approach the queen in shape of head and mandibles) seem 96 TWO CHAPTERS OX ANTS. to live a life of comparative ease, and have their food "brought to them by the minors. This may be the reason of the non-develop- ineiit of the teeth among the aristocracy. But how the same parent can produce such differing offspring — some born to a life of ease, with obsolete teeth, and others with well-developed teeth to do the work — is one of the mysteries in Nature. The only way to settle the point with regard to the man- dibles beyond dispute is to find the pupae or very young queens and soldiers, which I was unable to do during my stay in Florida. All the young were in the larval state. THE END. ^dS > "]>y of either will be sent for one year, postage />rr BAZAR will be sent gratis for every Club of FIVE JBSCRIBERS at $! 00 each, in one remittance; or MX Copies for $20 00, without extra copy: postage •repaid by the Publishers. Address HARPER & BROTHERS, NEW YORK.