on shallow lakes, lagoons, and miry marshes, and, unlike rails and gallinules, 

 they do not skulk and stick to cover, but stay almost always in the open reaches, 

 where they are exposed to the view of predatory birds and beasts. The adults 

 are black underneath and rich red-brown above, with pea-green wings. As 

 birds go, they are apt to be conspicuous, although not always easily discerni- 

 ble amidst the multitudinous sharp lights and shadows of the lab)Tinths of 

 lily pads over which they often walk. Watching a flock of jacanas feeding un- 

 der the noonday sun, one sees from a little distance mainly the black-breasted 

 adults — of the more daintily-colored, white-breasted young there seem to be only 

 two or three in the whole flock of a score or more. But when the horizontal 

 sun-rays of late afternoon or early morning stream across the marsh, behold a 

 revelation! The young, concealed till now by their counter shading, show up 

 in quantities, outnumbering the adults almost two to one. This is a most 

 beautiful and convincing exhibition of the power of obliterative shading, and 

 one which must leave a lasting impression on the mind of every observant person 

 who sees it. But it suggests also an interesting question — so interesting that, 

 though it leads us into the tabooed region of h)^othesis, we must be permitted 

 to discuss it briefly. Why are the adult jacanas deprived of the counter shad- 

 ing which served their youth so well? Adult gallinules also, it is true, lack 

 counter shading, but they are always alert to skip into deep cover at a moment's 

 notice, whereas the jacanas, as I have said, live in flocks, conspicuously ex- 

 posed, in the open tracts of lagoons and marshes, and rarely or never take to 

 cover unless wounded. Is it not highly probable that the strong spurs on 

 their wings have something to do with all this? May it not be that the 

 young, weak-spurred and inexperienced, need concealment in situations where 

 the adults, with their hard, sharp thorns, are well able to protect them- 

 selves?* Undoubtedly, the dark-hued parents must often serve to distract 

 the attention of predatory creatures from their obliteratively-colored but 

 defenseless young. Certain it is that these spurs are not, like those of cocks 



* There must, of course, be situations where the adults are as obliteratively colored as the young. — 

 A. H. T. 



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