368 University of California Publications in Zoology:  \Vou. 18 
hooklets small, sometimes pronged, ventral cilia short and appressed 
to barbule in inner vane, proximal dorsal cilia lobate, the others 
short and spiny. 
(5) Proximal barbules small and slender, ventral teeth inconspic- 
uous, pennulum rather stout, and shorter than base; well-developed 
hooked ventral cilia developed in outer vane in Cuculi, but these 
rudimentary in Psittaci. 
(6) Structure of body feathers mere simplification of that of 
remiges, the barbicels much reduced. 
(7) Down in most Cueul with small globular nodes, larger 
towards base of barbules, and pigment proximal to them; Psittaci 
with nodes shaped like eucalyptus fruit, and pigmented. 
12. Order CORACIIFORMES 
Plates 31-33 
This order includes a large number of diversified birds which 
may be regarded as forming a more or less natural connecting link 
between the Cuculiformes and lower birds on the one hand, and the 
Passeriformes on the other. Although some of the included fam- 
ilies are undoubtedly near the line of descent of the latter, others 
are to be regarded as very specialized offshoots, e. g., the Striges, 
and the Bucerotidae. The suborders Coraciae, Striges, Caprimulgi, 
Colii, Trogones, Cypseli and Pici, as given by Knowlton and Ridge- 
way (1909), are not of equal value. In discussing the structure 
of the feathers in this order, that of a species of the typical sub- 
order will be described in detail and the other families or groups 
in which important modifications occur with be taken up in order, 
regardless of the suborders into which they have been grouped. 
Throughout the order the plumules are more or less suppressed ; 
in the Alcedinidae they are dense in the apteria, but sparse in the 
pterylae; in Striges, Caprimulgi and Cypselidae they are present 
in the apteria only, while in all other forms they are absent en- 
tirely. The aftershaft is even more variable, beimg absent in some, 
e. g., Buceros, rudimentary in others, e. g., Meropidae, and very well 
developed in others, e. g. Trogones. 
a) Coracias affinis 
(1) Remex 
Shaft about as wide as deep; median ventral groove small and 
inconspicuous, striations on sides at junction of barbs slight. Rami 
