348 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



Boms." Fibrous materials that enter into the lining of nests include 

 fine strips of bark, fine grasses, tendrils, feathers, and horsehair. 

 A. T. Wayne (1910) collected several nests that were "profusely lined 

 with feathers." W. P. Proctor (MS.) mentions having seen a gnat- 

 catcher in northern Florida "picking the petals from dewberry blos- 

 soms [Rubus trivialis] for its nest." 



I was interested to discover what degree of availability determines 

 the selection of material for a particular nest. I had an old nest, a 

 mantel decoration much the worse for dust and age, of which I knew 

 the original location — it had been taken from a point about 20 feet 

 up in a medium-sized live oak that grew on the edge of a highway 

 right-of-way where it entered a wooded swamp. Pulling the nest to 

 pieces, I found it to be composed largely of oak catkins felted together 

 with plumed seeds and a kinky plant fiber, buff in color, that I could 

 not name at the time. Scattered through the mass were a few small 

 pieces of what appeared to be "sheet" spider web or fragments of 

 cocoons, but there was no vestige (even under a strong hand lens) of 

 the insect silk or spider web that had presumably been used to bind 

 the outer covering of lichens to the body of the nest. Actually, there 

 was no longer need for a mechanical binder since the lichens had 

 attached themselves firmly to their new foundation. The inner cup 

 of the nest was a felted structure, readily separable from the base 

 and from the outer, lichen-covered sheathing. It had been shaped 

 by a few stiff, wirelike grasses (unidentified) disposed through the 

 felted material almost like the reinforcing bars in an engineer's con- 

 crete structure, and the felting was composed entirely of the plumed 

 seeds and the kinky fiber and contained no catkins. Upon visiting 

 the original site at the usual season of nest building, I found (as I 

 knew I should) that the oak catkins and the lichens were obtainable 

 in unlimited quantity within inches of the spot where the nest had 

 been built. The plumed seeds proved to be from one of the broom- 

 grasses (Andropogon sp.), a small dried patch of which, still bearing 

 a few seeds late in the season, was within 10 yards of the base of the 

 nest tree — and I could find no more within a hundred yards in any 

 direction. The kinky buff fiber was discovered in inexhaustible 

 abundance along both sides of the right-of-way: it was the stem 

 "wool" of the cinnamon fern (Osmunda cinnamomea) . 



Measurements of two nests were kindly furnished by W. P. Proctor 

 (MS.). One was: outside, 2 inches diameter by 2% deep; inside, 1% 

 inches diameter by 1% deep. The other measured: outside, 2)i inches 

 diameter by 2}{ deep; inside, 1% inches diameter by 1% deep. The 

 striking feature of both these sets of figures is the difference between 

 the inner and outer depths — 1){ inches in the first nest and % inch in 

 the second. These differences represent the thickness of the founda- 



