Chapter 6: The "Itannia" or Horned Frog and the Ants
Animals are continually providing the interested observer with fresh material for study, and there are no limits to the surprises revealed by lifting merely a corner of the veil.
A strange, probably unique, experience occurred to me in my first encounter with the Brazilian “Itannia,” or horned frog.
We had, by dint of two and a half months of laborious effort, cut a way through the forest of Southern Brazil.
From San Pedro de Alcantara, in the province of Parana, we had crossed the Cola Militare and were working our way along the Rio Ivany, which is only navigable in a few places, through the densest, almost impassable virgin forest.
Once more it was evening, and before sundown we called a halt. I ordered camp to be pitched in a sheltered place at the forest edge, not far from the bank. Then everyone set to work with a will, pleased that rest was at hand.
Soon tents were standing; fires burning for my cooking-pot and those of my men; the muddy water of the river was dripping through the filters. A bathe was too much of a risk, so I spent a quarter of an hour being douched out of the animals’ drinking buckets. The dirty Indians never thought of washing. I knew that after supper there would be a great business of ridding one another of vermin.
The horses were set free to graze, and were crushing the succulent stalks of flowers and grass between their teeth.
The wind was rustling the age-old trees with a sound which soothed our overwrought nerves and limbs. Gay, brilliantly-hued birds, disturbed and excited, screamed over our heads; great lizards scuttled away as the firelight penetrated their hiding-places. No doubt somewhere in the neighbourhood a jaguar or puma was lurking. Giant snakes were also plentiful in this district.
A strange, fairly loud croak, that might have come from some hoarse raven, sounded not far behind my tent and awakened me from my dreams. It seemed to come, not from the air, but from the thick grass. It roused my curiosity.
Could it be some bird lying in distress somewhere among the grass, or had one fallen into the claws of some beast of prey and was crying for help? But the tone was too loud, too lusty.
I went out in search, and only had to go a few yards and part the branches of a bush to have my curiosity satisfied. Before my eyes was one of the most remarkable and rare creatures among the lower exotic animals.
A frog, about twenty centimeters long and quite as broad, of extraordinary, quite grotesque appearance, with irregular horn-like formations on its brilliantly coloured body, was sitting on a smooth path strewn with a few leaves, uttering these misleading cries, which now sounded like the wailing of a small child; and my astonishment was great when I saw that the frog was surrounded by two armies of giant ants engaged in desperate battle.
And yet, within a radius of twenty centimeters from the frog—I estimated the distance pretty accurately—the ground was free of ants; and not a single ant ventured into this area. Even the wounded and crippled in battle, which happened to reel feebly into the free space, turned back after a few steps, choosing rather to return to the turmoil of the fight than to approach the shrieking and distended batrachian.
The end of the grim struggle was at hand. I saw how a great portion of the ants fighting behind the frog began to retreat and were pursued only a short distance, while the victors who were left behind finished off their wounded enemies.
You cannot witness a battle between two swarms of ants without being astounded at the method with which they wage war. In columns, under the leadership of superior and subordinate officers, the two opposing nations advance upon one another, and a severe, blood-thirsty butchery begins. One cannot but admire in amazement the skill with which the individual divisions are led and manœuvered. Whenever a large number fall before the formidable nippers, new units at once replace them.
These insects all look identically alike, and it is marvelous how the opposing warriors can recognise one another. There must be differences of smell in the different swarms, for outwardly there are no distinguishing marks, even under the most powerful microscope.
What followed now was even more interesting. The free space round the itannia became alive with the victors, and then with a couple of leaps the frog went through and over the ant-armies towards me and I caught it.
Was it fear and horror that caused the frog to make so much noise; were his cries intended to spur on the fighters, or keep them away from his body?
The riddle is a difficult one to solve. On the following days I set the prisoner in places where ants were busily swarming, but he paid practically no heed to them; and once I saw him even pick some up with his tongue and taste them; but he soon spat them out again.
I afterwards had many opportunities of observing horned frogs, and also the lettered-frog, which is closely akin to the itannia. I once placed another prisoner between two armies of fighting ants, but he at once escaped with a great outcry; nor did the giant ants take the slightest notice of him.