THE NATURALIST ON THE RIVER AMAZONS. 



and commence grubbing with their fore feet 

 and snouts around the roots of herbage, search- 

 ing for insect larvae. On the slightest alarm 

 they will scamper off ; their tails cocked up in 

 the air as they waddled awkwardly away, evi- 

 dently an incn ml> ranee to them in their flight. 

 Next to the birds and lizards, the insects 

 of the suburbs of Para deserve a few remarks. 

 I will pass over the many other orders and 

 families of this class, and proceed at once to 

 the ants. These were in great numbers every- 

 where, but I will mention here only two 

 kinds. We were amazed at seeing ants an 

 inch and a quarter in length, and stout in 

 proportion, marching in single file through 

 the thickets. These belonged to the species 

 called Dinoponera grandis. Its colonies con- 

 sist of a small number of individuals, and are 



Sniiba or Leaf-carrying Ant. 1. Working minor ; 

 2. Working-major; 3. Subterranean worker. 



-established about the roots of slender trees. 

 It is a stinging species, but the sting is not 

 rso severe as in many of the smaller kinds. 

 There was nothing peculiar or attractive in 

 the habits of this giant among the ants. 

 Another far more interesting species was the 

 iSaiiba ((Ecodoma cephalotes). This ant is 

 .seen everywhere about the suburbs, march- 

 ing to and fro in broad columns. From its 

 habit of despoiling the most valuable culti- 

 vated trees of their foliage, it is a great 

 .scourge to the Brazilians. In some districts 

 it is so abundant that agriculture is almost 

 impossible, aud everywhere complaints are 

 heard of the terrible pest. 



The workers of this species are of three 

 orders, and vary in size from two to seven 

 lines ; some idea of them may be obtained 

 from nlhe accompanying wood-cut. The 

 true working-class of a colony is formed 

 by the small-sized order of workers, the 

 worker-minors as they are called (Fig. 1). 

 The two other kinds, whose functions, as 

 we shall see, are not yet properly understood, 

 have enormously swollen aud massive heads ; 

 3n one (Fig. 2). the head is highly polished ; 

 in the other (Fig. 3), it is opaque and hairy. 

 The worker-minors vary greatly in size, some 

 being double the bulk of others. The entire 

 body is of very solid consistence, and of a 

 pale reddish-brown color. The thorax or 

 middle segment is armed with three pairs of 

 sharp spines ; the head, also, has a pair of 

 similar epines proceeding from the cheeks 

 behind. 



In our first walks we were puzzled to ac- 

 count for large mounds of earth, of a differ^, 



ent color from the surrounding soil, which 

 were thrown up in the plantations and 

 woods. Some of them were very extensive, 

 being forty yards in circumference, but not 

 more than two feet in height. We soon 

 ascertained that these were the work of the 

 Saiibas, being the outworks, or domes, which 

 overlie and protect the entrances to their vast 

 subterranean galleries. On close examina- 

 tion, I found the earth of which they are 

 composed to consist of very minute granules, 

 agglomerated without cement, and forming 

 many rows of little ridges and turrets. The 

 difference in color from the superficial soil of 

 the vicinity is owing to their being formed 

 of the undersoil, brought up from a consider- 

 able depth. It is very rarely that the ants 

 are seen at work on these mounds ; the en- 

 trances seeem to be generally closed ; only 

 now and then, when some particular work is 

 going on, are the galleries opened. The en- 

 trances are small alid numerous ; in the large 

 hillocks it would require a great amount of 

 excavation to get at the main galleries ; but I 

 succeeded in removing portions of the dome 

 in smaller hillocks, and then I found that the 

 minor entrances coc verged, at the depth of 

 about two feet, to one broad elaborately- 

 worked gallery or mine, which was four or 

 five inches iu diameter. 



This habit in the Saiiba ant of clipping and 

 carrying away immense quantities of leaves 

 has long been recorded in books on natural 

 history. When employed on this work, their 

 processions look like a multitude of animated 

 leaves on the march. In some places I found 

 an accumulation of such leaves, ail circular 

 pieces, about the size of a sixpence, lying 

 on the pathway unattended by ants, and at 

 some distance from any colony. Such heaps 

 are always found to be removed when the 

 place is revisited the next day. In course of 

 time I had plenty of opportunities of seeing 

 them at work. They mount the tree in mul 

 titudes, the individuals being all worker- 

 irinors. Each one places itself on the sur- 

 face of a leaf, and cuts with its sharp scissor- 

 like jaws a nearly semicircular incision on 

 the upper side ; it then takes the edge be- 

 tween its jaws, and by a sharp jerk detaches 

 the piece. Sometimes they let the leaf drop 

 to the ground, where a little hrap accumu- 

 lates, until carried off by another relay of 

 workers ; but, generally, each marches off 

 with the piece it has operated upon, and HS 

 all take the same road to their colony, the 

 path they follow becomes in a short lime 

 smooth and bare, looking like the impression 

 of a cart-wheel through the herbage. 



It is a most interesting sight to see the vast 

 host of busy diminutive laborers occupied on 

 this work. Unfortunately they choose cul- 

 tivated trees for their purpose. This ant rs 

 quite peculiar to tropical America, as is the 

 entire genus to which it belongs ; it some- 

 times despoils the young trees of species 

 growing wild in its native forests ; but seems 

 to prefer, when within reach, plants import- 

 ed from other countries, such as the coffee 

 and orange trees. It has not hitherto been 



