CHAPTER X 



BACKGROUND-PICTURING ON OBLITERATIVELY SHADED BIRDS, CONTINUED. 

 REED PATTERNS AND OTHER MARKINGS OF BITTERNS. THE COLORATION 



ONE more pronounced modification of the ' dead-grass' type of picture- 

 pattern must be considered. This is the picturing in a near view of 

 straight, erect reeds, which exists on the necks and heads of several herons, 

 notably the American Bittern (Botaurus lentiginosus), which shall serve as our. 

 example. Many herons are wont to stand motionless, with neck and head 

 extended and erect, and in the bitterns this habit reaches its climax. The 

 American Bittern will stand for an hour at a time in a swampy meadow, with 

 scarcely a movement of its erected, straight and stick-like neck and head, 

 terminating in the long, sharp bill, which points directly upward. When, as 

 is pretty frequently the case, the neck and head in this position project above 

 the reeds or grasses, they look, in certain lights, and from a sufficient distance, 

 like a pointed stick or stub. This fact has been commented on by many 

 writers, all of whom, it seems, have thought it a sufficient explanation of the 

 Bittern's curious trick. Though we admit that the stick-aspect is sometimes 

 most pronounced, and must therefore have a bearing on the significance of 

 the habit, we are convinced that this has another function of far greater im- 

 portance, namely, the display in correct position, and with the clearness 

 gained by depressed feathers, of the reed-stripes on the upper neck, which 

 extend sharp and unbroken over the head, and are even continued on the 

 bill. The following extract from my journal, recording my first recognition 

 of the high obliterative efficacy of these stripes, contains some details which 

 make it worth quoting: "But if this [stick-mimicry] were the explanation, 

 what would be the function of the finely developed, sharply contrasted stripes 



OF HERONS IN GENERAL 



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