After shooting the Toucans I leaned my gun against a patch of black moss on a tree trunk. To my astonishment the moss whirled outward and back, and then I saw it was a host of caterpillars crowded as densely as they could be in a patch three feet high and forming a semicircle about the six-inch trunk. They were covered with black, branched, stinging hairs, with two longer tufted ones on the segments near the head. As Francis said, “Um wurrum’s hairs bite hard!” I began experimenting with their reaction motions. I found that any _sst_ sound or hiss, the snapping of fingers, whistling, hand clapping, or pounding on the metal or wood of my gun, caused absolutely no response on the part of the caterpillars. No matter how close to the creatures or how loud or sudden was the sound, unless they were touched they did not move. On the contrary, any utterance of such sounds as _bis!_ _bow!_ _bing!_ _buzz!_ even when so low as hardly to rise above a whisper, caused every caterpillar of the many hundreds to react as one. The head with the long tufted appendage was jerked quickly backward, then down, and on the edges of the mass from side to side. Those in the centre, because of their position, had only the up and down flick. The effect as a whole was indescribable. An inconspicuous growth of moss was transformed like a flash into a seething, rearing mass of waving caterpillars. A suggestion, altogether theoretical, is that the reaction to the buzzy sounds may hint that the chief danger feared by these caterpillars is the fatal buzz of the wings of the ichneumon fly. This evening we added baboon and bill-bird to our venison, and were surprised to find the former tender and by no means devoid of taste. The Toucans were tough, but more than one of us came back for a second helping of “howler”—in spite of the cannibalistic chaff with which we were regaled! [Illustration: FIG. 134. PHONETIC CATERPILLARS.] The rain had increased in amount successively during the last three days and to-night a new sound was added to our nocturnal chorus—the Bubbling or Gurgling Frogs, which, by the score, vented their joyful emotions in energetic gulps from the jungle at the edge of the clearing. APRIL 1st.—Having missed finding Trumpeters yesterday, Francis promised them for to-day and we took a long tramp full of incident as usual. We circled to the north, swinging around beyond the first two valleys and then turning and describing a second curve intersecting the first. Two of the Jungle Wrens or Quadrille Birds[125] sang their incomparable strains, each with a theme of its own. The first had two phrases which it uttered alternately, thus; [Music]