320 University of California Publications in Zoology (Vou. 18 
are characterized by a series of transverse rings which evidently 
have a tendency to break up the light and deepen the red color 
produced by the diffused pigment. The proximal barbules remain 
practically unchanged. 5 
Ajaja ajaja, representing the Plataleidae or spoonbills, resembles 
Plegadis very closely. Both Plegadis and Ajaja have the ventral edge 
of the rami serrate. The similarity of the barbules of the back 
feathers to similar ones of Mycteria is shown by plate 20, figure 27a, 
as compared with plate 20, figure 23c. 
c) Down 
The down barbules of Mycteria americana and of other 
Ciconiidae are long, frequently over 2.5 mm., and are very slender 
and filamentous, with minute inconspicuous prongs, or none what- 
ever, at the nodes. In the Ibididae and Plataleidae, on the other 
hand, the down barbules are rather short, usually under 1 mm. in 
length, and very stout and coarse, the internodes with longitudinal 
ridges and grooves, and the nodes with well-developed prongs. A 
down barbule of Guara rubra is shown on plate 23, figure 101. 
ad) Relationships 
The Ciconiae form the middle section of the Ciconiiformes, the 
Steganopodes being below them and the Ardeae and Phoenicopteri 
above. Undoubtedly their closest relatives are the herons, with 
which they are joined by such intermediate forms as Balaeniceps 
and Scopus, the feathers of which I have been unable to obtain for 
study. The Phoenicopteri appear to connect the Ciconiae with the 
Anseres. No relation whatever is shown by the structure of the 
feathers to the Limicolae or to typical Gruiformes. 
e) Summary 
The Ciconiae are characterized as follows: 
(1) Barbules much more numerous on distal than on proximal 
vanule. 
2. Distal barbules with base of moderate size relative to prox- 
imals, with moderate, lobate ventral teeth ; pennulum stout and heavy, 
with 6 or 7 moderate-sized, progressively longer hooklets; ventral 
cilia more or less appressed, straight, usually blunt; on the imner vane 
about three well-separated, stout, basal dorsal cilia, followed by less 
