Page:The New International Encyclopædia 1st ed. v. 07.djvu/547

* FEAST OF ROSE GARLANDS. 495 FEATHER. FEAST OF ROSE GARLANDS, 'I'm painting by Diirer in the Prague Museum (1506), representing the Virgin crowning the Emp while the Child places a wreath on the Pope's head, and angels scatter roses over the kneeling attendants, tian influence. FEAST OF WEEKS. See Weeks, Feast of. FEASTS. See Festivals. FEATHER. A river with numerous head- streams which rise in northeastern California, in the Sierra Nevada Mountains, and flow in a generally southwest <lirrcti.ui. uniting in Butte County, a few miles northeast of Oroville (Map: California, (' 2). From this point the Feather runs nearly due south, receiving YiiIki River and Bear Creek on the east, and joining the Sacra mento in Sutter County, about twenty miles above Sacramento. The stream is aboul i«n hun- dred miles long, but is navigable only to Marys- ville, a distance of 30 miles. II Hows through one of the richest gold-fields in the State, and the scenery is magnificent along its upper course. observable in the stem of a feather. "The middle stratum is the thickest, and i- le feather itself, while the outermost forme a transparent and coherent cylindrical sheath, which im-i the growing feather, giving it its well-known The painting bears marks of Vene spine like appearance ['pin-feather*], until, ing off as semi', ii | of the young product" j V T < wton). This is tory "i i in- in i growl h, but t he process i stanl tally t he a me foi all feal hers . hieh ari e from the same pulps. For an au periodical shedding and renewal of plun Uoi.i i.c;. Sec also I, i eoument; Skeij ro A c plete feather consists of a I vane. The shaft is made up of the cylindrical hollow barrel or calamus which extends to the beginning of the vane, where it is succeeded by the opaque, pith-filled squarish stem or rachis; in many birds the feather also bears upon the inside of its calamus an aftershaft, or hypo rachis, which is a counterpart of the main feather, and occasionally, as in the emeu, maj equal it. The vane or web is the blade lil e i pansion along the sides of the distal part of the feather, and consists of several elements: FEATHER (AS. feper, Ger. Feder; connected a row of horny lamelli, called barbs or rami, with Lat. penna, feather, Gk. irrephr, pteron, which are wedge-shape in section, the thin edge wing, from irh-eaBat, petesthai, Skt. pat, to fly), being turned toward the bird's body. Their number One of the numerous complicated outgrowths varies: a crane's wing-feather, 14 inches long, from the skin forming the protective coat or plumage of birds, and peculiar to this class. They exist in great variety, and serve various ends in bird-economy, and are applied to diversi- fied uses in human arts and industries., Origin and Structure or Feathers." For the probable origin of plumage as a characteristic and essential element in the class of birds, and its influence on their evolutionary develop- ment, see Bird. In the individual birds, as now known, the first sign of feathers appeals in the embryo, about the fifth day of incubation of the egg, as slight , backward- leaning, conical pimples which arise from the mesoderm. (See Em- bryology. ) Such a pim- ple gradually sinks into the skin, forming a fol- licle with the papilla rising in its centre : and the walls of this follicle and surface of the papil- la are formed of Mal- pighian cells. This cen- tral papilla forms the 'feather - pulp,' and its upper portion becomes changed and filled with blood, forming the nu- tritive organ of the feather. In the space be- tween the pulp and the walls of the follicle the feather is molded, bv the hardening and splitting off of the three superficial layers of cells. The innermost and thinnest stra STRUCTURE OF A FEATHER. Perei five view ol a portion of two adjacent harbs (6, b), looking from the shaft toward tl Igeol the vane; /"/. posterior or distal barbules. overlapping and locking into the proximal or anterior barbules (ftp) of the next barb. has about 650 in its inner web. These barbs bear on each side similar lamelli. called barbules or radii, very minute, and exceeding a million in number for such a feather as. the crane's; and each one of these has its upper margin turned over, like a flange, toward the rachis; further- more, the end of each radius on that side of the ramus which looks toward the tip of the feather is split up into a fringe of hooks that reach over PARTS OF A FEATHER. e, calamus or 'barrel,' part of which has been been cut horn; - pith ' cups (p). con- tinue] Cat p') through the umbilici-form pit, whence aris.s the aftershaft (a),- r. ruins; ii-. web or vane, each line here representing a Mbarb' orramus; d, downy portion. BARBICELS AND HAMULI. Oblique section through the proximal barbules in a plane parallel to the distal barbules of the other illustration: ft, ft. bartis: bd, distal barbules; a. a, a, barbicelsand ham- uli of the ventral side: e, barbicele of the dorsal side, with- out hamuli; ft/>, barbicels of the proximal barbules. the radii of the next forward row. and hook on to their flanges, thus connecting them all into . -■-- ........ w uu^i* ......^.v... inno tuuutvuiii; ohiii ,111 im< pun forms a transparent sheath for the pulp, and the firm, springy, and almost air-tight fabric pre Persists ultimately as the series of thin caps sented by most surface or 'contour' feathers
 * n, ;iv bo show the series of