266 FRANCIS H. HERRICK 



common chimney swift in building (see fig. 8) uses only slender 

 dead and brittle twigs, which are snapped oft" on the wing; they 

 are further glued to their support and to one another by means 

 of viscous saliva, and with the uniformity of a basket weaver's 

 art. (For example of nest showing greater variation in mater- 

 ials, but perfect in type see fig. ii.) 



Appropriation of nest materials illustrated. While certain 

 birds, as we have seen, go far at times to find suitable nest 

 materials, and make use of definite kinds, the majority take 

 from their immediate environment only, and adapt whatever 

 it has to offer to their needs. The robin in nesting time may 

 be seen flying high with ball of mud in bill, having travelled a 

 quarter of a mile or more for the requisite substance, but it does 

 not follow that under like conditions all w^ould do the same; 

 their conduct, as we have shown, will depend upon a number 

 of variable factors, but the rule in this instance is to take what 

 comes nearest to hand. 



The great herring gulls of the Duck Islands probably travel 

 at least thirty miles in search of food, but in building their 

 nests they draw only upon the resources of their island, and 

 mainly from an area of very short radius; again I have known 

 certain arctic terns on Matinicus Rock to gather everything 

 used in building their nest within the compass of a square yard, 

 or even to limit themselves to the leaves and pebbles within 

 reach of bill, while sitting on the chosen site. The ospreys on 

 Plum Island, on the other hand, were formerly kncnvn upon 

 occasion to levy tribute from a distant shore. 



The appropriation of nesting materials from the nearest source 

 was well illustrated by red eyed vireos and cedar waxwings in 

 central New Hampshire. Now it is the practise of these vireos 

 to line their nests either with fine bark strippings or with old 

 needles of the white pine where both abound, but in other parts 

 with bast alone. The question arises whether the species is 

 split up into certain gens, one favoring this and another that 

 material, or is it a case of individual preference, dependent upon 

 the environment mainly; we cannot answer definitely, but are 

 inclined to the latter view. A nest of this vireo referred to 

 (No. 2, table 3), was built in a maple tree, close to a dwelling 

 house; the frame of this nest was made entirely of grape vine 

 bark, the finest strippings being worked into the inner wall. 



