338 University of California Publications in ZooJofjij [Vol. 13 



Unfortunately, i have been unable to secure feathers of the first 

 and fourth suborders for examination, and the relationships sug- 

 gested by their feather structure cannot, therefore, be discussed. 

 The other two groups, Galli and Turnices, tliough in superficial 

 appearance very similar, differ in so many details of feather struc 

 ture that they may more advantageously be considered separately. 



I. Suborder Galli 

 PI. 26, Figs. 42-47 

 Though containing a very large number of species and genera, 

 this suborder forms a fairly compact and well-defined group. In 

 general they are characterized by the restriction of the plumules to 

 the apteria, and by the variability of the aftershaft. In some 

 members of the group, e. g., Bonasa, the latter is better developed 

 than in any other group except Casuariiformes, while in others, e. g. 

 Pavo, it is very small and almost rudimentary. 



a) Oallus domesticus 



(1) Remex 



Shaft slightly wider than deep, with a broad, conspicuous ventral 

 groove; calamus, in contrast to the condition found in Anseres, 

 short, not greatly inflated, its caliber less than that of the shaft. 



Vanes firm, harbs of the inner vane set about 18 per centimeter, 

 those of outer vane considerably less, especially in the primaries. 

 Vanules with barbules very close set, about 40 distals and 32 prox- 

 imals per millimeter in a typical portion of the feather, this number 

 of proximals being larger relative to the number of distals than 

 in most water-birds. 



Inner vane. — Distal barbules (pi. 24, fig. 42a) with base about 

 0.26 mm. in length by 0.04 mm. in width, the peunulum about the 

 same length. Base rather broad and quadrangular, with usually 3 

 ventral teeth, these in the form of broad lobes, very thin and film- 

 like. Nuclei in a conspicuously diagonal line, on account of the 

 short, broad form of the base, with its broad ventral teeth. Pen- 

 nulum with 6 to 8 booklets of moderate size, progressively increas- 

 ing in length, not slender with enlarged hooks, as in Anseres, but 

 stouter basally. Ventral cilia of moderate size, not flexible or 

 appressed, but in the form of stout, strongly curved, hooklike 

 processes, decreasing in size toward the tip, but relatively well 

 developed on the whole length of the pennulum ; 3 or 4 sharp, 

 spinelike, dorsal cilia, not, however, highly modified as broad lobate 

 or hoodlike projections. More distal cells of the pennulum with 

 short, pronglike, rudimentary dorsal cilia. 



Proximal barbules (pi. 24, fig. 42&) with slender base, about 

 0.6 mm. long by 0.05 mm. Avide, with a series of short, pointed, 

 lobate ventral teeth. Pennulum remarkably short, especially on 



