First lesson in zoology : adapted for use in schools . t,half natural size. (One- and under these heads are many varieties (Figs. 207, 208)In the toes of the perching birds the muscles and their tendons are so arranged that they automatically maintain while the bird is asleep a grasping position on the perch by means of the birds own most striking external feature of birds is the presence of feathers; no reptile, on the one hand, or mam-mal, on the other, is clothed with feathers. The ordinary feathers are called jwewM as, or contour feathers, as they determine by their arrangementt
First lesson in zoology : adapted for use in schools . t,half natural size. (One- and under these heads are many varieties (Figs. 207, 208)In the toes of the perching birds the muscles and their tendons are so arranged that they automatically maintain while the bird is asleep a grasping position on the perch by means of the birds own most striking external feature of birds is the presence of feathers; no reptile, on the one hand, or mam-mal, on the other, is clothed with feathers. The ordinary feathers are called jwewM as, or contour feathers, as they determine by their arrangementthe outline of the body. They are,like hairs, developed in sacs in theskin ; the quill is hollow, partly im-bedded in the skin; this merges intothe shaft, leaving the outgrowths oneach side called barls, which sendoff secondary processes called bar-bules. The barbules and booklets(barbicels. Pig. 209) are commonlyseiTated, and end in little hooks bywhich the barbules interlock (). Down is formed of feathers with soft, free barbscalled Via. 209.—Feather, sh, shaft;V, vanes; A, barbule, with (6c;the barbicels. 202 FIB8T LESSONS IN ZOOLOGY. The differences between the feathers, especially of thewings and back, aid us in discriminating the different kindsof birds. The student should have a dead or stuffed birdbefore him, and, with the aid of Fig. 210, learn the namesof the different kinds of feathers, as well as the other terms
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1894
