370 



NORTH AMERICAN BIRDS. 



large enouij:]i to receive one acorn at a time. Tliey are packed in, one above 

 tlie other, until the cavity is full. How tUd these Woo(lj)eckers first learn 

 to thus use these storehouses, hy nature closed against them? The intelli- 

 trent instinct that enabled this l)ird to solve this i)roblem Saussure reurarded 

 as not tlie least surprising feature. With its beak it pierces a small round 

 hole tiirough the lower j)ortion into the central cavity, and thrusts in acorns 

 until the hollow is tilled to the level of the hole. It then makes a second 

 l)ening higher u\), and tills the space below in a like manner, and so pro- 



o 



ceeds ui>til the entire stalk is full. Sometimes the space is too small to re- 

 ceive the acorns, and thev have to be forced in bv blows from its beak. In 

 other stalks there are no cavities, and then the Woodpecker creates one for 

 each acorn, ibrcing it into the centre of the pith. 



The labor necessary to enable the bird to accomplish all this is very' con- 

 siderable, and great industry is reipiired to collect its stores ; but, once col- 

 lected, tlie storehouse is a very safe and convenient one. Mount Pizarro is 

 in the midst of a barren desert of sand and volcanic dehris. There are no 

 oak-trees nearer than the Cordilleras, thirty miles distant, and therefore the 

 collecting and storing of each acorn required a flight of sixty miles. 



This, reasons Saussure, is obviously an instinctive preparation, on the 

 part of these l»irds, to provide the means of su})porting life during the arid 

 winter months, when no rain falls and everything is parched. His observa- 

 tions were made in A])ril, the last of the winter months ; and he found 

 the Woodj)eckers withdrawing food from their depositories, and satisfied 

 himself that the birds were eating the acorn itself, and not the diminutive 

 magufots a few of them contained. 



The ingenuity with which the bird managed to get at the contents of each 

 acorn was also quite striking. Its feet being unfit for grasping the acorn, it 

 digs a hole into the dry bark of the yuccas, just large enough to receive the 

 small end of the acorn, which it inserts, making use of its bill to s[)lit it 

 open, as with a wedge. The trunks of the yuccas were all found riddled 

 with these holes. 



There are several remarkable features to be noticed in the facts observed 

 by Saussure, — the provident instinct which prompts this bird to lay by 

 stores of provisions for the winter ; the great distance traversed to collect 

 a kind of food so unusual for its race ; and its seeking, in a spot so remote 

 from its natural abode, a storehouse so remarkable. Can instinct alone 

 teach, or have exi)erience and reason taught, these birds, that, better far than 

 the bark of trees, or cracks in rocks, or cavities dug in the earth, or any 

 other known hiding-place, are these hidden cavities within the hollow stems 

 of distant plants ? AVhat first taught them how to break through the flinty 

 coverings of these retreats ? By what revelation could these birds have 

 been informed that within these dry and closed stalks they could, by search- 

 ing, find suitable places, protected from moisture, for preserving their stores 

 in a state most favorable for their long preservation, safe from gnawing 



