﻿88 ON THE CLASSIFICATION OF BIRDS. 



and third are of the same length ; but there is a falling 

 off among the white-eyed warblers (Zosterops), where the 

 first quill begins to shorten, and this leads on to a gradual 

 shortening of the two next quills, until the form of the 

 wing becomes rounded. The second description of wing 

 which is termed pointed, is seen in the hooded and 

 other genuine crows, in the Drongo shrikes, and in 

 many of the flycatchers of the old world (Muscicapince}. 

 In most of these the wing is long, either reaching to 

 the middle of the tail or beyond it, but the first quill is 

 little more than half the length of those which are 

 longest, which are generally the fourth and fifth. An 

 inspection of the wing of the hooded crow will at once 

 give a more correct idea of the relative length of the 

 three first primary quills than the most exact description 

 could do : it will be perceived that the fourth quill is 

 the longest, the third and fifth being equal to each 

 other, but rather shorter than the fourth. There is 

 but little variation from this structure in the Drongo 

 shrikes, which, nevertheless, according to Le Vaillant, 

 possess great rapidity of flight. He states that these 

 birds, natives of Southern Africa, assemble together in the 

 evening upon trees, from which they make frequent and 

 rapid excursions, much in the manner of swallows, after 

 bees and other peaceful insects which are wending home 

 from their day's labour. 



(81.) Emarginated wings are obviously formed for 

 rapid flight, but they have no fixed character in the 

 proportion of the exterior primaries ; for in some groups 

 the first quill is as long as any of the others, while in 

 other instances, the first, second, and third quills are 

 gradually shortened, as we see in the Drongo shrikes ; the 

 true distinction of an emarginate wing consists of a 

 sudden notch, or sinuosity, more or less abrupt, which 

 is found on the margin of the inner shaft of the longest 

 quills. This notch in the true falcons is situated near 

 the end of the shaft(^. 44 a.), but in the sparrow-hawk, 

 and other of the " ignoble " hawks, it is placed at the 

 base. (6) The flight of these latter birds is well known 



