1916] Chandler: Structure of Feathers 321 
specialized ones, except in Leptoptilus, where there are only 2, and 
these close together. 
(3) Proximal barbules with large bases, inconspicuous ventral 
teeth, a short but broad and tapering pennulum, and no ventral 
cilia developed on outer vane. 
(4) Ventral edge of outer rami of primaries serrate in Ibididae 
and Plataleidae, but smooth in Ciconiidae. 
(5) Body feathers with barbules as in remiges, but more elongate 
and slender; never any flexules. 
(6) Down barbules in Ciconiidae long, slender, and filamentous, 
with small inconspicuous prongs or none at all; in Ibididae short, 
stout and heavy, longitudinally ribbed, and with well-developed 
prongs at the nodes. 
Ill. Suborder ARrpDEAE 
Pl. 20, Figs. 20-22 
As stated above, the typical Ardeae are readily distinguishable 
from the Ciconiae, but Balaeniceps and Scopus combine the char- 
acters of both groups in such a way that the characterization of 
either is very difficult without allowing for these exceptions. 
Unfortunately I have not been able to obtain feathers of either of 
these genera for study, in order to find out whether their feather 
structure adheres to the typical ardean type or approaches that of 
the Ciconiae. Having no data concerning either of these two out- 
lying forms, nor of Cochlearius, the present section deals only with 
the Ardeidae, including the herons, egrets and bitterns. Their 
general epiphyological characteristics are as follows: (1) plumules 
confined to the apteria, (2) powder down present, (3) aftershaft 
present, and (4) lores naked. 
a) Ardea herodias 
(1) Remexr 
Shaft and rami very similar to those of Ciconiae, the shaft, if 
anything, slightly deeper than wide, with V-shaped ventral groove, 
and fine striations on side. Rami not considerably deepened, even on 
outer vane, the pith not more than a single layer in thickness and 
the ventral edge not serrate or furnished with villi. Distal vanule 
with about 30 barbules per millimeter, proximal vanule with about 
18 per millimeter. 
Inner vane.—Distal barbules (pl. 20, fig. 20a) with small base, 
about 0.26 by 0.04 mm. with relatively very large, leaf-like ventral 
teeth so shaped and arranged as to form a single, large, blunt, 
