. A manual of zoology. Zoology. 534 CHORDATA existence in many feathers of a rudimentary featlier, tlie hyporachis, or ajler-shaj't, aitadied to tlie scape below. In contour feathers the barbs are, to a great extent, united into a i>ane. Thev lie close together and paraUel, right and leftof the shaft, each rejieating in miniature the entire feather, the barb haWng branches or barhulcs, which, over- lapping the barbules of adjacent barbs, give the vane its close texture. The vane is held together by minute honks on the barliules of one barb interlocking with those of the next. Doicn fcallicr
. A manual of zoology. Zoology. 534 CHORDATA existence in many feathers of a rudimentary featlier, tlie hyporachis, or ajler-shaj't, aitadied to tlie scape below. In contour feathers the barbs are, to a great extent, united into a i>ane. Thev lie close together and paraUel, right and leftof the shaft, each rejieating in miniature the entire feather, the barb haWng branches or barhulcs, which, over- lapping the barbules of adjacent barbs, give the vane its close texture. The vane is held together by minute honks on the barliules of one barb interlocking with those of the next. Doicn fcallicrs (pliinia) dilfer from contour feathers in the absence of hooks and the loose arrangement of the barbs. Since feathers consist of cornihed epithelium and these cells arc held firmly (only in pmcdcr doivn is there a gradual loss), they, like the scaly coat of the snakes and lizards, must be molted vearlv and replaced bv new. Young birds or embryos have only down feathers. Later the contour feathers arise in regularly arranged fcalhcr Iraiis, or picrylic, fietween which are apten'a in which no contour feathers appear (fig. 5S3). Since the contour feathers overlap like shingles, tliev form a firm coat beneath which the down and semiplumes form a warm coat. Besides these covering feathers (coverts, or hrtnt-c;. fig. 584, D) there are the longer feathers of tlie wing, the rciiugrs. and the tail feathers, or rcclriccs [S-). The larger remiges form tlie chief part. Fig. 5S5.âWing skeleton of storlc (from Gegenbaur). c, c', carpalia of llrst row, /;, humerus; 111, hissed metacarjials ami carpals of second row; />-/>", phalanges of first three fingers; r, radius; 11, ulna. of the â v\'ing; they spring from the part of the limb corresponding to the hand (carpus, metacarpus, phalanges) and are known as primaries {HS). while the sccaiidaries (.is), arising from the forearm, are shorter. These are overlapped at the base by the covcrls [D, D', D") and by the paraplcriuni (
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectzoology, bookyear1912
