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Show 104 DOMESTIC PIGEONS. CHAP. VI. a1 1 t 11 0 cases wh J.C ]1 I h."...v o collected) that hardly a single well-a~ certaincd in tance is known of hybrids botw en two true spec1·e s of p1· gcons b cm· g £ rtile , inter se ' or even when crossed with one of their pure parents. 0 0 0 S . t1l -E -clud.ino- certain important charactor1stJC drffor-tx n !J· x b . h h th on cs, th chi f rae s agree most closely both ':Jt cac o or and. with 0. livia in all other respects. As pr vwu ly observed, ll · tly 001a ar cmmen ·.".', ble ·, all dislike ·to perch or . roo. st, and refnsc to build. in tr cs; all lay two eggs, and th1s JS not a univcr al rule with the CJolumbidre; all, as far as I can hear, require the sam time for hatching their eggs; all can endure the arne groat range of climate; all prefer the same food, and arc pa sionately fond of salt; all exh~bit (with t~e as crted exception of the :finnikin and turner, whJCh do not d1ffcr much in any other chara tor) tho same peculiar gc~tures when courting tho ~males; and all (with tho ~xccptwn o~ trumpeters an(l langhcr , which likewise do not d1ffcr much. m any ot~cr chara ·tor) coo in the same peculiar mann r, unhkc :he vo1ce of any other wild pigeon. All the coloured breeds dJs~lay the same peculiar metallic tints on the br ast, a charaytcr far from g ncral with pigeons. Each race presents nearly the same range of variation in colour; and in most of the races we have the same ingular correlation between the development of down in the young and tho future colour of plumage. All have the proportional length of their toes, and of their primary wing-feathers, n arly the same,-characters which are apt to differ in the several members of tho Columbid::e. In those races which present some remarkable deviation of structure, such as in tho tail of fantails, crop of pouters, beak of carrier. and tumblers, &c., the other part r.emain nearly unaltered. Now every naturalist will admit that it would be scarcely possible to pick out a dozen natmal species in any Family, which should agree clo ely in habits and in general structure, and yet should differ greatly in a few cha-many eggs were produced, but all were barr n. At Paris, hyhrids have been rni ed (I sid. Geoffroy Sflint Hilaire, • I·Iist. Nat. Gencmlc,' tom. iii. p. I 0) from 'l'urtur cturitus with '1'. can-,.. ba.yenRis o.ud witl1 T. suratensis ; but nothing is said of their fertility. At the Zoologiral Gm·dcns of London the Goura coronata o,nd vicloriw produced a hybrid, which paired with tho pure G. coronata, and laid several eggs, but the prnvcd burrcn. In 1860 Columba gymnophlhalmos and maculosa produced hybrids in these same gardens. CHAP. VI. TIIEIR REVERSION IN COLOUR. 195 ractcrs alone. This fact is explicable through the doctrine of natural selection; for each succe ·sivc mochfication of sku ·ture in each natural species is prcsorvccl, solely bccau. e it is of service; and such modification. wh n largely accumulated imply a groat ·hang in the habits of life, and this will almo t certainly lead to other changes of structure tP..roughout the whole organisation. On the other hand, if the several races of the pigeon have been produced by man through selection and variation, we can r atlily under tand how it is that they should still all res mblc each other in habits and in those many characters which man has not cared to modify," whilst they diffor to so prodigious a degree in those parts which have struck his eye or pleas cl his fancy. Besides the points above enumerated, in which all the domestic race resemble C. Iivia and each other, there is one which deserves special notice. The wild rock-pigeon is of a slaty-blue colour; the wings are crossed by two black bars; the croup varies in colour, being o·enerally white in the pigeon of Em·ope, and blue in that of India; tho tail has a black bar close to the end, and the outer webs of the outer tail-feathers are edged with white, except ncar the tip . These combined characters are not found in any wild pigeon beside 0. livia. I have looked carefully through th great collection of pigeons in the British Museum, and l find that a dark bar at tho end of the tail is common; that tbe white edging to the outer tail-feathers is not rare; but that tho white croup is extremely rare, and tho two black Lars on the wings occur in no otbcr pigeon, excepting the alpine C. leueonota and 0. rupestris of Asia. Now if we turn to the domestic races, it is highly remarkable, as an eminent fancier, Mr. Wicking, observed to m~ that, "vhcnevcr a blue . bird appears in any mce, the wings almost invariably show the double black bars.23 The primary wingfeathers may be white or black, and the whole body may be 23 There is one exception to the rulo, nam(']y in a sub-vo.riuty of the swallow of German origin, which is figured by N enmei tcr, o,nd was shown to me by Mr. Wieking. This bird is blue, but bo,s not tho black wing-bars; for our object, however, in tracing tho descent of the chief races, this exception signifies tho lCS!! as the swallow npproaches closely in structure to C. livia. In many sub-varieties, ihc black bars me replaced by bars of various colours. Tho figures given by Neumeister are sufficient to ~how 1.hnt, if tho wings alone o.re blue, the bluck wing-bars appear. 0 2 |