188 DOMESTIC PIGEOXS. Chap. VI 



gone a considerable amount of variation, as in the toy-pigeons 

 We shall moreover presently see how eminently favourable cir- 

 cumstances have been for a great amount of modification in the 

 more carefully tended breeds. 



The reasons for concluding that the several principal races 

 have not descended from so many aboriginal and unknown 

 stocks may be grouped under the following six heads : — Firstly 

 if the eleven chief races have not arisen from the variation of 

 some one species, together with its geographical races, they must 

 be descended from several extremely distinct aboriginal species • 

 for no amount of crossing between only six or seven wild forms 

 could produce races so distinct as pouters, carriers, runts 

 fantails, turbits, short-faced tumblers, jacobins, and trumpeters. 

 How could crossing produce, for instance, a pouter or a fantail, 

 unless the two supposed aboriginal parents possessed the re- 

 markable characters of these breeds ? I am aware that some 

 naturalists, following Pallas, believe that crossing gives a strong 

 tendency to variation, independently of the characters inherited 

 from either parent. They believe that it would be easier to 

 raise a pouter or fantail pigeon from crossing two distinct 

 species, neither of which possessed the characters of these races, 

 than from any single species. I can find few facts in support ' 

 of this doctrine, and believe in it only to a limited degree ; but 

 in a future chapter I shall have to recur to this subject. For 

 our present purpose the point is not material. The question 

 which concerns us is, whether or not many new and im- 

 portant characters have arisen since man first domesticated 

 the pigeon. On the ordinary view, variability is due to changed 

 conditions of life ; on the Pallasian doctrine, variability, or the 

 appearance of new characters, is due to some mysterious effect 

 from the crossing of two species, neither of which possess the 

 characters in question. In some few instances it is credible, 

 though for several reasons not probable, that well-marked races 

 have been formed by crossing; for instance, a barb might 

 perhaps have been formed by a cross between a long-beaked 

 carrier, having large eye-wattles, and some short-beaked pigeon. 

 That many races have been in some degree modified by crossing, 

 and that certain varieties which are distinguished only by pecu- 

 liar tints have arisen from crosses between differently-coloured 



