318 Unwwersity of California Publications in Zoology ‘Vou. 138 
(4) Breast feathers with flexules developed on terminal por- 
tion of barbs of breast feathers. 
(5) Down smooth and filamentous, little if any over 1 mm. long. 
Il. Suborder Crconrar 
Pl. 20, Figs. 23-27 
Constituting the second suborder of the Ciconiiformes are the 
storks and ibises, which, together with the Ardeae, form a compact 
and well-defined group. Although the typical Ardeae are readily 
distinguishable from typical Ciconiae, there are a number of more 
or less intermediate forms which make their characterization by 
other characters as well as by epiphyology very difficult. Ex- 
cluding Balaeniceps and Scopus, which combine characters of both 
groups, the Ciconiae are distinguished from the Ardeae by the fol- 
lowing characteristics: (1) absence of powder down, (2) even 
distribution of plumules in both pterylae and apteria, and (3) 
feathered lores. The aftershaft is very variable, being present, 
rudimentary, or absent in different genera. 
a) Mycterva americana 
(1) Remex 
Shaft stout and square, about as deep as wide, with broad, V- 
shaped ventral groove, and fine striations on sides where barbules 
are attached. Rami not greatly deepened at junction with shaft 
but deeper than usual in Steganopodes. Pith cells more than a 
single layer thick, and ventral edge of rami of both outer and inner 
vanes without villi. Distal vanule with barbules greatly outnum- 
bering those of proximal vanule, the barbules about 40 per milli- 
meter on former, only 18 per millimeter on latter, this difference ac- 
companied by great difference of angle of insertion of barbules on 
ramus. 
Inner vane—Distal barbules (pl. 20, fig. 23a) small relative to 
proximals; base of moderate size, about 0.35 by 0.05 mm., with 
fairly large, lobate ventral teeth, frequently blunt and_ slightly 
incised at tip; pennulum characterized by stout heavy form; 
hooklets numerous, 6 or 7 in number, moderately stout, and pro- 
eressively increasing a great deal in length; ventral ciha rather 
poorly developed, present all the way to tip of pennulum, straight, 
and appressed to barbule; basal dorsal cilia stout, blunt, and spine- 
like, well separated from each other, the first one always the largest ; 
usually three such stout barbicels developed, the following ones 
becoming more and more like the ventral ones. Proximal barbules 
(pl. 20, fig. 23b) with very large bases, about 0.7 mm. long by 0.07 
mm. wide with a series of broad, triangular ventral teeth projecting 
very little beyond the ventral contour of barbule; pennulum re- 
