1916] Chandler: Structure of Feathers 349 
umbilicus very high, much higher than wide, and egg-shaped in 
cross-section. Kami moderately broad at junction with shaft, pith 
more than one cell thick, the ventral ridge rather narrow, less than 
one-seventh total width of ramus, its ventral edge smooth. 
Inner vane—Distal barbules (pl. 26, fig. 50a) set about 28 per 
millimeter. Base short and broad, about 0.24 mm. by 0.06 mm., 
ventral teeth of moderate size, broad and lobate, their tips often 
inconspicuously jagged, or very slightly bifurcated. Pennulum 
considerably longer than base, rather broad, hooklets 5 or 6, mod- 
erately slender and progressively longer, but hooklet cells so short, 
and each successive hooklet curved so much farther distal, that distal 
ones reach no farther ventral than proximal ones; ventral cilia 
slender, but slightly curved, all but first two or three appressed to 
pennulum; more proximal dorsal barbules spinelike, especially first 
two, more distal ones well developed, but slender, curving forward. 
Proximal barbules (pl. 26, fig. 50c) relatively large, set about 17 
per millimeter, base about 0.73 mm. long by 0.07 wide, with 5 or 6 
rather narrow, pointed, conspicuous ventral teeth; pennulum some- 
what shorter than base but over half as long, flattened and mod- 
erately broad proximally, its tip slender, with rudimentary barbicels. 
Outer vane—Distal barbules (pl. 26, fig. 506) differmg from 
those of inner vane only in loss of proximal dorsal cilia, other 
details of both base and pennulum similar to those of inner vane. 
Proximal barbules (pl. 26, fig. 50c), except at tip of barb, exactly 
similar to those of inner vane. Towards tip of barb ventral teeth 
become separated, and assume shape similar to those in Butorides 
(pl. 20, fig. 216), 1. e., short curved .barbicels, intermediate in form 
between typical ventral teeth, as exemplified in more basal proximal 
barbules (pl. 26, fig. 50c), and typical hooked ventral cilia, as in the 
terminal proximal barbules of the outer vane in Rallus (pl. 26, 
fig. 52c). 
(2) Other Feathers 
Back feathers have distal barbules with rather elongate, slender 
base, the ventral teeth with bifurcation or jaggedness of tips more 
pronounced. Pennulum very long, 0.05 mm. or over, giving velvety 
effect to feathers. Both dorsal and ventral cilia similar to those of 
distal barbules of inner vane of remex. Proximals (pl. 26, fig. 50d) 
with slender base, about 0.65 mm. long by 0.05 wide, ventral teeth 
reduced in size and number, and pennulum relatively shorter than 
im remiges. 
Scapular feathers especially modified as ornamental plumes, a 
large part of outer vane, and some of inner vane, with discrete, 
i. e., non-adhering, barbs, which curve outward. This condition is 
accomplished merely by the breaking off of distal barbules imme- 
diately beyond base, thus destroying interlocking apparatus. Tips 
of proximal barbules also usually imperfect. 
Breast feathers have structure of barbules on basal two-thirds 
of middle barbs very similar to back feathers, except reduction of 
all barbicels of distal barbules (pl. 26, fig. 50e) and shortening 
of pennulum of proximals. On distal third a rather sudden transi- 
tion occurs in both kinds of barbules to type shown in plate 26, 
fieure 50f. No differentiation between base and pennulum, the 
