360 LIFE HISTORIES OF NORTH AMERICAN BIRDS. 



The nests are generally well hidden, and are rather bulky but compactly 

 built structures, averaging from 7 to 8 inches in outer diameter by 4 to 4£ 

 inches in depth; the inner cup measures about 3£ to 4 inches in diameter by 

 2£ inches in depth. Outwardly they are composed of small twigs (thorny ones 

 being preferred), bark, moss, lichens, paper, rags, strings, wool, leaves, and dry 

 grasses, the various materials being well incorpoi-ated and sometimes cemented 

 together with mud, but not always; the lining is usually composed exclusively 

 of fine rootlets. Occasionally the Blue Jay will take the nest of another species 

 by force. 



Mr. W. E. Loucks, of Peoria, Illinois, writes: "A nest of a pair of Robins, 

 built in an elm tree, was stolen and appropriated by a pair of these birds. It 

 was fitted up to suit their needs, and eggs were deposited in it before the eyes of 

 the angry Robins." 



Judge J. N. Clark, of Old Saybrook, Connecticut, found a nest of the Blue 

 Jay, in the spring of 1883, in a rather curious place. It was built among the 

 roots of a large tree that had been prostrated by the wind, turning up a large 

 mass of roots, with the adhering soil. Near the top of this mass, some 8 feet 

 from the ground, under the border of the turf, which had curved over, making 

 a screen, the nest, with its five eggs, was neatly hidden from view. 1 



The number of eggs to a set varies from tln'ee to six; sets of four or five are 

 most often found, and an egg is deposited daily. Both sexes assist in incubation, 

 which lasts from fifteen to sixteen days. The young grow rather slowly, and 

 are fed on insects, worms, and animal food. They often leave the nest before 

 they are fully feathered, and when scarcely able to fly. At this time they fre- 

 quently betray their presence by their incessant clamor for food, never appearing 

 to get enough to satisfy their enormous appetites. The parents are exceedingly 

 devoted to them, and are close sitters. Instances have been recorded where a 

 female Blue Jay allowed her head and back to be stroked while sitting on her 

 eggs. The eggs of the Blue Jay vary greatly in their ground color. In some 

 this is olive green, olive buff, and pea g'reen; in others it is plain buff color, or 

 again cream and vinaceous buff. This is irregularly spotted and blotched with 

 different shades of browns and lavender, the markings being generally heaviest 

 about the larger end. A peculiar set of three eggs in the United States National 

 Museum collection has a pale bluish-green ground color, with only a few rather 

 large blotches of slate and lavender about the larger end, and one of these eggs 

 is almost unspotted. The shell is smooth, close grained, rather strong, and occa- 

 sionally slightly glossy. The eggs are usually ovate in shape. 



The average measurement of one hundred and thirty-five eggs in the United 

 States National Museum collection is 28.02 by 20.44 millimetres, or about 1.10 

 by 0.81 inches. The largest egg of the series measures 30.48 by 21.59 milli- 

 metres, or 1.20 by 0.85 inches; the smallest, 25.15 by 20.07 millimetres, or 0.99 

 by 0.79 inch. 



1 Ornithologist and Oologist, Vol. 8, 1883, p. 78. 



