34 The Wilson Bulletin — No. 82. 



bark to reinforce it and hold it in shape. Within all is the 

 lining, covering the bottom and the lower part of the sides 

 of the cavity. 



The materials used vary a great deal in exact kind, but 

 the general type of things necessary is the same in all. For 

 the framework of the base and cup, long strips of some ma- 

 terial, five to seven inches long and one-sixteenth to one-fourth 

 inch wide, are required. These are often of grapevine bark, 

 and milkweed inner bark is also much used. The framework 

 may be composed entirely, or almost entirely, of grapevine 

 bark, of milkweed bark, of grass-stems or weed-stems ; or 

 it may be composed of all of these, together with hickory, 

 elm or raspberry bark. 



Apparently the materials nearest at hand are used. Two 

 nests taken from elm trees in a slashing containing many 

 milkweeds and few other sources of supply, have the frame- 

 work almost entirely of milkweed bark, with a little elm 

 bark in one (Nos. 1 and 4 in the table). Another (No. 6), 

 from a slashing" containing no milkweeds, but near a large patch 

 of wild grapevines, has its framework entirely of their bark. 



The framework is often fastened together with cobwebs. 

 The felting, which fills all the interstices of the framework 

 and fastens it to the crotch, hangs out in rags, giving the 

 nest a fantastic tattered appearance. It is composed mostly 

 of comparatively coarse " vegetable wool." The felting also 

 contains always some fine grass-stems or twigs and cobwebs, 

 usually a dried leaf or two of the tree the nest is built in, 

 often a little dried moss or some hickory leaf-stems, and I 

 once found a good deal of real wool. 



The " vegetable wool " mentioned before, is composed of 

 very finely shredded vegetable fibers. The most common 

 substance in it is the outer bark of the milkweed, although 

 it often contains also a little bark or grass substance. The 

 milkweed plant is common in all kinds of places, and its dried 

 stem often stands till a year or two after its death. On these 

 dead stems the thin outer bark hangs in little ragged shreds, 

 inviting attention. The inner bark is very tough and strong 



