﻿EXTERNAL ANATOMY. TARSAL SCALES. 115 



groups which represent them. Lastly, we may notice 

 the tarsi of the parrots, which are covered, both on the 

 front and sides, with numerous small scales, never touch- 

 ing each other, but being so disposed, that their inter- 

 stices, or the spaces between them, resemble the lines of 

 a net; such a tarsus, therefore, is said to be reticulated. 

 In Platycircus, Pezoporus, and Leptolophus, these scales 

 are much closer to each other than in the macaws, and 

 in some of the neighbouring genera, where they are 

 perfectly oval. We need not, however, proceed into the 

 variations of the anterior scales of the other orders, since 

 other characters are found in the Grallatores and Nata- 

 tores, which are quite sufficient for the correct discrimi- 

 nation of the subordinate groups, without having recourse 

 to these. 



(107.) The lateral scales of the tarsus, as already 

 mentioned, protect the sides ; but, although they are not 

 always present, their office is supplied by the anterior 

 scales, which are then extended round the leg, so as 

 nearly to envelope it. The tarsi of many groups are 

 thus constructed; but the tyrant flycatchers are the most 

 perfect examples that can be mentioned. The only 

 scales on the tarsus of the Tyr annus intrepidus, or the 

 kingbird of the Americans, are those here termed the 

 anterior : they consist of five unequal pieces, and en- 

 velope the tarsus so completely as nearly to meet on the 

 back part, and thus preclude the necessity of either the 

 lateral or posterior series ; the common robin has the 

 lateral scales, no less than the anterior, of one entire 

 piece, except that there is the slight appearance of a 

 small division at each extremity, and the two lateral 

 scales on each tarsus are so closely brought together on 

 the hind part, that there is no room for the posterior 

 series. The scales, however, we are now describing, are 

 very conspicuous among the falcons and shrikes. In 

 the Falco sparverius they are much smaller than the 

 anterior, and are regularly pentangular; in the true 

 butcher-birds (Laniance) and the African bush shrikes 

 (Malaconotus, Jig. 60. a) they are entire, while in the 

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