THE REDISCOVERED COUNTRY 345 



There is so much of value in it that it is a pity his natural 

 enthusiasm for so pretty a hypothesis should have carried 

 him beyond all reason. Thus he seriously maintains that 

 the wavy marks on the ends of a duck's breast and side 

 feathers are imitations of ripple marks on the water wherein 

 the duck swims; and that for that reason they tend to con- 

 ceal the duck from its ^'natural enemies." A moment's 

 reflection, without the necessity of actual experiment, shows 

 that such fine markings are invisible at a very short dis- 

 tance, and that within the distance of their visibility the 

 duck is very plainly in sight to anything with any eyes at 

 all.* He instances the scarlet tanager, and can, of course, 

 easily prove that it is often invisible in thick woods. He 

 attempts to tell us this is because of the black and red 

 markings of that brilliant bird, forgetting that when the 

 scarlet tanager is invisible any other bird whatsoever would 

 be equally invisible. Or that the thin white transverse 

 stripes of the eland tend to break up that animal's bulk, 

 whereas, of course, as every one who has ever seen an eland 

 knows, the stripes are quite invisible beyond forty yards. 

 And any one who has been within forty yards of an eland 

 and not seen it is either in completely concealing cover or 

 should depart for the nearest oculist. Mr. Thayer's 

 interest in working out possible applications! of this fasci- 

 nating idea has led him into a mental point of view very 

 like that of an enthusiastic lawyer toward a technical case. 

 Each quite honestly rather loses sight of the verities. 



*A duck in the water is a mass, always! Yes; I have looked at them 

 from above! 



t For a great number of instances, see his book. Most of them beg the 

 question and imply such close proximity to the animal before the markings 

 can be seen at all that the mass of the beast could not possibly be overlooked. 



