272 



FOWLS. 



Chap. VII. 



In the eight first birds, belonging to distinct breeds, in this table, we 

 see a decided reduction in the weight of the bones of the wing. In the 

 Indian Frizzled fowl, which cannot fly, the reduction is carried to the 

 greatest extent, namely, to thirty-three per cent, of their proper propor- 

 tional weight. In the next four birds, including the Silk-hen, which is in- 

 capable of flight, we see that the wings, relatively to the legs, are slightly 

 increased in weight ; but it should be observed that, if in these birds the 

 legs had become from any cause reduced in weight, this would give the 

 false appearance of the wings having increased in relative weight. Now 

 a reduction of this nature has certainly occurred with the Burmese Jumper, 

 in which the legs are abnormally short, and in the two Hamburghs and 

 Silk fowl, the legs, though not short, are formed of remarkably thin and 

 light bones. I make these statements, not judging by mere eyesight, but 

 after having calculated the weights of the leg-bones relatively to those of 

 G. bankiva, according to the only two standards of comparison which I 

 could use, namely, the relative lengths of the head and sternum ; for I do 

 not know the weight of the body in G. bankiva, which would have been 

 a better standard. According to these standards, the leg-bones in these 

 four fowls are in a marked manner far lighter than in any other breed. 

 It may therefore be concluded that in all cases in which the legs have not 

 been through some unknown cause much reduced in weight, the wing-bones 

 have become reduced in weight relatively to the leg-bones, in comparison 

 with those of G. bankiva. And this reduction of weight may, I appre- 

 hend, safely be attributed to disuse. 



To make the foregoing table quite satisfactory, it ought to have been 

 shown that in the eight first birds the leg-bones have not actually in- 

 creased in weight out of due proportion with the rest of the body ; this 

 I cannot show, from not knowing, as already remarked, the weight of the 

 wild Bankiva.? 4 I am indeed inclined to suspect that the leg-bones in 

 the Dorking, No. 2 in the table, are proportionally too heavy ; but this 

 bird was a very large one, weighing 7 lb. 2 oz., though very thin. Its 

 leg-bones were more than ten times as heavy as those of the Burmese 

 Jumper ! I tried to ascertain the length both of the leg-bones and wing- 

 bones relatively to other parts of the body and skeleton ; but the whole 

 organisation in these birds, which have been so long domesticated, has 

 become so variable, that no certain conclusions could be reached. For 

 instance, the legs of the above Dorking cock were nearly three-quarters 

 of an inch too short relatively to the length of the sternum, and more than 



in Dorkings as 557 : 248, or as 

 100 : 44 ; and so on for the otlier breeds. 

 We thus get the series of 62, 52, 44 for 

 the relative weights of the wing-hones in 

 G. bankiva, Cochins, Dorkings, &c. And 

 now taking 100, instead of 62, for the 

 weight of the wing-bones in G. bankiva, 

 we get, by another rule of three, 83 as the 

 weight of the wing-bones in Cochins ; 

 70 in the Dorkings ; and so on for the 



remainder of the third column in the 

 table. 



7 4 Mr. Blyth (in ' Annals and Mag. of 

 Nat. Hist./ 2nd series, vol. i., 1848, p. 

 456) gives 3| lb. as the weight of a full- 

 grown male G. bankiva ; but from what 

 I have seen of the skins and skeletons 

 of various breeds, I cannot believe that 

 my two specimens of G. bankiva could 

 have weighed so much. 



