. Key to North American birds. Containing a concise account of every species of living and fossil bird at present known from the continent north of the Mexican and United States boundary, inclusive of Greenland and Lower California, with which are incorporated General ornithology: an outline of the structure and classification of birds; and Field ornithology, a manual of collecting, preparing, and preserving birds. Birds; Birds. Fig. 45. â Zygodactyle foot of a woodpecker, Hylotomm pileatus, nat. size. Fig. 44.âSyn- dactyle foot of klng- fifiher, nat. size. one either; seen in those perching h
. Key to North American birds. Containing a concise account of every species of living and fossil bird at present known from the continent north of the Mexican and United States boundary, inclusive of Greenland and Lower California, with which are incorporated General ornithology: an outline of the structure and classification of birds; and Field ornithology, a manual of collecting, preparing, and preserving birds. Birds; Birds. Fig. 45. â Zygodactyle foot of a woodpecker, Hylotomm pileatus, nat. size. Fig. 44.âSyn- dactyle foot of klng- fifiher, nat. size. one either; seen in those perching hirds which scarcely use their feet for progression, hut simply for sitting motionless, (c) The zygodactyle or yoke-toed modification has been sufS- ciently noted (fig. 45). It was formerly made much of, as a sccmsorial or climl)mg type of foot, and an absurd "order" of birds has been called Seomsores. But many of the zygodactyle birds do not climb, as the cuckoos; while the most nimble and adroit of climbers, such as the nuthatches and creepers, retain a typically pas- serine foot. The " scan- sorial" is simply one modification of the insessorial plan, and has little clas- sificatory significance, â no more than that attaching to the particular con- dition of the iasessoiial foot (d) which results from elevation or versatility of the hind toe, as in some Cypselidee and GaprimulgidcB. This is an abnormality which has received no special name; it is generally associated with some little webbing of the anterior toes at base, which is a de- parture fi-om the true inses- sorial plan, or with abnormal reduction of the phalanges of the third and fourth toes, as explained above (figs. 40, 41). (e) The raptorial is another modification of the insessorial foot. It is advantageous to a bird of prey to be able to spread the toes as widely as possible, that the talons may seize the prey like a set of Fig. 46.âRaptorial foot of a hawk, Accipiter cooperi, nat. size. gr
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1894
