146 



THE YOUNG 



NATUEALIST. 



occur together in any other species. 

 Now most of the domestic races " breed 

 very true '* ; that is, white fantails pro- 

 duce white fantails ; black barbs pro- 

 duce barbs, and so on ; and the pro- 

 duction of markings, peculiar to the 

 original type, by crossing birds from 

 which these marks. or peculiarities had 

 been entirely eliminated, can only be 

 accounted for on the principle of rever- 

 sion, a subject on which we may enlarge 

 on another occasion. One experiment 

 had better be told in Mr. Darwin's own 

 words. " I crossed some white fan- 

 tails, which breed very true, with some 

 black barbs — and it so happens that 

 that blue varieties of the barb are so 

 rare that I never heard of one instance 

 in England ; and the mongrels were 

 black, brown, and mottled. I also 

 crossed a barb with a spot, which is a 

 white bird with a red tail, and a red 

 spot on the forehead, and which notor- 

 iously breeds very true ; the mongrels 

 were dusky and mottled. I then 

 crosged one of the mongrel barb -fantails 

 with a mongrel barb-spot, and they pro- 

 duced a bird of as beautiful a blue 

 colour, with the white lines, double 

 black wing bar, and barred and white- 

 edged tail feathers as any wild rock 

 pigeon ! " Mr. Darwin tells us that 

 there is no instance of crossed des- 

 cendents reverting to an ancestor of 

 foreign blood " removed by more than 

 a dozen or twenty generations. We 

 certainly know that there has been no 

 ancestor of foreign blood within hun- 

 dreds or perhaps thousands of genera- 

 tions, and a reversion like this is only 



explainable on the assumption that all 

 these races spring from that common 

 ancestor so well known to bear these 

 peculiarities. Another strong argument 

 in favour of this position is the perfect 

 fertility with each other, of all our 

 domestic breeds. It it also known that 

 tbe Eock Dove is easily domesticated 

 now, and when so reared agrees in 

 many of its habits with the domestic 

 breeds, as they do when run wild with 

 the habits of their supposed progenitors. 

 But our space will not permit us to 

 enlarge, and we must reserve for 

 another paper our remarks on the 

 marked differences of those birds that 

 figure on our illustrative plate. 



TO CORRESPONDENTS. 



All communications to be Bent to J. E. Eobson, 15 

 Northgate, Hartlepool; or to S. L. Mosley Beau- 

 mont Park, Huddersfield. 



Subscriptions for Vol. III. are now due. 

 Weekly numbers or monthly parts, 6s.; 

 with plain plates ; or 8s. with coloured 

 plates. The latter cannot be obtained 

 through the booksellers, but any one can 

 have their plates coloured on application 

 to the Editors. 



D.D., Edinbro*. — We believe neither of the 

 catalogues you name are procurable now. 

 We have in contemplation an Illustrated 

 Catalogue of British Beetles, of which we 

 hope shortly to be able to announce 

 particulars. 



EXCHANGE. 



Duplicates. — Imagines of Zonaria, male 

 and female. Desiderata.— Very numerous 

 N.B.— If the specimens be desired alive, 

 please write early.— R. A. Eraser, Seafield, 

 Abbotsford Road, Great Crosby. 



