340 FRANCIS H. HERRICK 



has gone on for hours. Indeed, so great is the violence of these 

 motions that often the tendency at first is to scatter rather 

 than consohdate the scanty materials; in a word the pecuHar 

 molding movements seem to be begun before they are needed. 

 We shall later see that this is only partially true, and that it is 

 through these very movements that the nest is firmly secured 

 and adapted to its site. In molding, the head and wings usually 

 go up, and the tail down, as already remarked, but the tail 

 is sometimes held vertical when the bird rests upon its fore 

 breast and neck. While watching nest building in this species 

 on a former occasion I thought that the wrists of the wings 

 w^ere used as an aid to the bill in drawing the materials up to 

 the body, but it was not the case in this instance. Movements 

 of the wings and tail simply partake of the general movements 

 of the feet and body, and evidently serve for balancing; at times 

 such a bird seems to be almost standing on its head. 



At the intervals between the molds the robin uses her bill 

 quickly and decisively in drawing in towards her breast the 

 loose or overflowing materials, often indeed with a violent 

 snap of the bill, and this bird was seen to snap viciously at the 

 leaves which overhung the nest and stood in her way. After 

 the first hour or so of building there may be as much stubble 

 on the ground as on the nest site, but this is not always the case ; 

 such waste material is invariably neglected w^hen on the ground , 

 but if hanging from the limb it is frequently, though not always, 

 the subject of special attention, and is drawn into the nest. 

 With this partial exception every increment is used as it is 

 brought, and there is no sorting of materials or discarding what 

 is once chosen. The molds often follow so rapidly that it is 

 difhcult to count them, the interval between each being limited 

 to the time required by the bird to rise, turn, and settle again. 

 Then long pauses may occur, the bird sitting low, and remaining 

 quiet as if resting from fatigue. Later in the course of the 

 process w^hen the walls have risen, these pauses become still 

 more pronounced, when the robin seems to be trying " the 

 fit " of her nest, or to make the molding process more effective. 

 In this case the male took no direct part in nest building, and 

 the female always worked alone, and as a rule in perfect silence. An 

 air of secrecy characterizes all the movements of the pair, 

 especially of the female from the beginning, broken only by 



