. 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 . Fig 55. — Actual section of the body in the thoracicregion of a bird. N, neural canal; //, hamal canal; c,centrum of a dorsal vertebra; hy, hypapophysis; (I,diapophysis ; z, zygapo

This image could have imperfections as it’s either historical or reportage.

. 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 . Fig 55. — Actual section of the body in the thoracicregion of a bird. N, neural canal; //, hamal canal; c, centrum of a dorsal vertebra; hy, hypapophysis; (I, diapophysis ; z, zygapophysis ; >i.s-, neural spine; r, pleurapopliysis, or vertebral part of a free rib, bearingu, uncinate process or epipleura; rr, hajniapophysisor sternal part of the same; st, section of sternum orbreast-bone (ha;mal spine). Designed by Dr K. W.Shufeldt, U. S. A. for an indefinite period through a hole in the humerus. Pneumaticity is not directly nornecessarily related to power of Hight; some birds which do not fly at all are more pneumaticthan some of the most buoyant. (On the general j)neiunaticity of the body see beyond underhead of the respiratory system.) Fio. 54. — Ideal plan of the double-ringed body of avertebrate. X, neural canal; //, hiemal canal; the bodyseparating them is the centrum of any vertebra, bear-ing e, an epapoi»hysi.-<, and y, a hypapophysis; n, n, neu-rapophyscs; d, d, diapop