of the mountain kind), opposed to the more or less vertical body-bands, call 

 for a word of comment. They are an example of 'secantly' obliterative mark- 

 ing as distinguished from pure and simple picture-pattern. Striped up and 

 down, the legs would continue the body's depiction of standing reeds or tufts 

 of grass, but they might alsp look like an animal's legs, for their true form and 

 general trend would be obscured but little. The legs, like the body, must be 

 cut crosswise by secant stripes, if they are to be fitly disguised. As was ex- 

 plained in Chapter XIII, such stripes achieve their full. effect only when 

 aided by corresponding background-markings. Though the zebra walks 

 amid upright grasses, etc., crisscrossing and horizontal stems and blades are 

 of course common enough in his haunts to yield the required amount of co- 

 operation to his essentially 'secant' horizontal leg-bands. When the zebra 

 is lying down, with legs outstretched, these transverse leg-bands have of 

 course a vertical direction, like the body-markings. This, perhaps, is the 

 position which best favors, in the aggregate, the proper working of his ob- 

 literative pattern. Still another detail of these wonderful harlequins' cos- 

 tumes which demands especial notice is the delicately striped head-pattern. 

 This is worn in almost equally high development by both zebras. It is by 

 every test a picture-pattern. For, just as in the case of the picture-patterned 

 birds (Chapter III, p. 32), this head-pattern of the zebra's is much smaller 

 and finer than that of the body, as if to match a striped background decidedly 

 reduced by distance — ^just such a one as the head, being the highest part, 

 must normally have in relation to the lower body. Considering birds alone, a 

 skeptic might suggest that the smallness of the head-pattern may be merely 

 the simple physical consequence of the smallness of the hesid-jeathers; but 

 such a theory would break down when confronted with the fact that there is 

 a like proportion in the sizes of pattern between the heads and bodies of 

 obliteratively colored hairy mammals. A single feather often contributes 

 the whole of an important spot, or even several spots, to the general pattern, 

 so that small feathers might mean small markings; but patterns made with 

 hair are very different. It takes many hundred crowded hairs to make a 



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