PIC A RLE: PICA RI AN BIRDS. 539 



feet is, that the claw of the hind toe is smaller, or at most not larger, than that of the third 

 toe ; and on the whole the hind toe itself is inconsiderable, weak if not wanting, not always 

 perfectly incumbent and apposable. The wings, endlessly varied in shape, agree in possessing 

 ten developed primaries, of which the first is rarely spurious or very short. (Notable excep- 

 tions to this occur in the Pici with spurious first primary, and in the Indicatoridce, with only 

 nine primaries.) A very general and useful wing-character is, that the coverts are larger and 

 in more numerous series than in Passeres ; the greater coverts being at least half as long as 

 the secondary quills they cover, and sometimes reaching nearly to the ends of these quills. 

 This is the common case among lower birds, but it distinguishes most of the Picaria; from 

 Passeres; it is not shown, however, in the Picidce and some others, as the Indicator idoe, Meya- 

 Ifemidce, and Rhamphastidce. The wing is quintocubital as a rule (with variability in Alcedi- 

 nidte and some Cypselidce'). The tail is indefinitely varied in shape, but the number of its 

 feathers is a good clue to Picarue. There are not ordinarily more than ten perfect rectrices, 

 and occasionally there are only eight, as in the Anis (Crotophaga') ; the AVoodpeckers have 

 twelve, but one pair is abortive ; there are twelve, however, in the Kingfishers, Puff'-birds, 

 Indicators, and some others ; ten or twelve indifierently in the Motmots. Pulviplumes occur 

 in the Leptosomatidce an«l Podargidce. The bill shows numberless modifications in form, and 

 lias its own specialization in nearly every family ; it assumes some of the most extraordinary 

 sliapes, as in the Hornbills and Toucans, and is seldom of the simjde style seen in a Thrush or 

 Finch; it is never hooked and cered, as in Parrots and Birds of Prey, nor soft and swollen at 

 the nostrils, as in Pigeons. 



With this sketch of some leading features of the group (it will <niable the student to recog- 

 nize any Picarian bird of this country at least, and that is my main object), I pass to the 

 consideration of its subdivision, with the remark that a precedent may be found for any con- 

 ceivable grouping of the families that is not perfectly preposterous, and for some arrangements 

 that are nearly so. As well as I can judge from the material at my command, and relying 

 upon authority for data that I lack, the provisional arrangement adopted in the 2d-4th editions 

 (tf the Key must be entirely remodelled. Such is especially the case with the '' Cuculiform"' 

 Picarians, which I justly stigmatized (p. 446) as " a mixed lot requiring to be reconstructed 

 by exclusion of some of the fiimilies given as entering into its composition.'' There are at 

 least 24 Picarian families, seven of them North American, rouglily divisible into three groups 

 or series, which I ft)rmerly called Cgjjsclifonnes, Cnculifornies, and Piciformes, answering to 

 tlie CgpselomorjjhfB, Coccygomorphce, and Celeomorphcc of Huxley, or the so-called " orders '' 

 Macrochires, Coccyges, and Pici of the A. 0. U. But I am now satisfied that we can best im- 

 jirove up(Mi these divisions by efiiicing their alleged boundaries and remapping tlie 24 families 

 liy redistributing them directly into several more than three suborders or superfamilies. Such 

 ran be satisfactorily established, primarily upon stnmg anatomical grounds, secondarily U{)on 

 good external characters. The structural modifications most serviceable for classification are : 

 ]iresence or absence of the ambiens muscle ; the disposition of the digits and especially of their 

 Hexor tendons ; conformation of the bony palate, sternum, and bones of the wing; presence or 

 absence of colic cfeca, as curiously related to the condition of the elpeodochon ; and various 

 peculiarities of tlie pterylosis, such as the presence or absence of aftersluifts, pulviplumes, and 

 tuft on the oil-gland, condition of the dorsal and ventral tracts, number of remiges and roc- 

 trices, etc. The arrangement of the carotid arteries is also to be taken into account. Details 

 of external form are insignificant in comparison with such morphological characters as those 

 just indicated, and may even bo deceptive; fi)r the superficial resemblance is sliglit between 

 some chisely related families, and conversely. Thus, the great helmeted II(»rnbills are specially 

 related to the small slender-billed lIoo]>oes; the Toucans, witli their enormous bills, behmg to 

 the series vvhidi includes the Barbels, I'uti'-birds. Jacaiiiars, and Woodpeckers; and otlier sucii 

 instances could be cited. 



