Sheer color alone is powerful enough, but when heightened by contrast, it becomes still more effective, and I seemed to have secured, with two barrels, a cotinga and its shadow. The latter was also a full-grown male cotinga, known to a few people in this world as the dark-breasted mourner (_Lipaugus simplex_). In general shape and form it was not unlike its cousin, but in color it was its shadow, its silhouette. Not a feather upon head or body, wings or tail showed a hint of warmth, only a dull uniform gray; an ash of a bird, living in the same warm sunlight, wet by the same rain, feeding on much the same food, and claiming relationship with a blazing-feathered turquoise. There is some very exact and very absorbing reason for all this, and for it I search with fervor, but with little success. But we may be certain that the causes of this and of the host of other unreasonable realities which fill the path of the evolutionist with never-quenched enthusiasm, will extend far beyond the colors of two tropical birds. They will have something to do with flowers and with bright butterflies, and we shall know why our "favorite color" is more than a whim, and why the Greeks may not have been able to distinguish the full gamut of our spectrum, and why rainbows are so narrow to our eyes in comparison to what they might be. Finally, there was thrown aside all finesse, all delicacy of presentation, and the last lingering feeling of temperate life and nature was erased. From now on there was no confusion of zones, no concessions, no mental palimpsest of resolving images. The spatial, the temporal,--the hillside, the passing seconds,--the vibrations and material atoms stimulating my five senses, all were tropical, quickened with the unbelievable vitality of equatorial life. A rustling came to my ears, although the breeze was still little more than a sensation of coolness. Then a deep whirr sounded overhead, and another, and another, and with a rush a dozen great toucans were all about me. Monstrous beaks, parodies in pastels of unheard-of blues and greens, breasts which glowed like mirrored suns,--orange overlaid upon blinding yellow,--and at every flick of the tail a trenchant flash of intense scarlet. All these colors set in frames of jet-black plumage, and suddenly hurled through blue sky and green foliage, made the hillside a brilliant moving kaleidoscope.