GROWTH AND SEXUAL GENESIS. 455 



rarely breed more than once in a season, we find that the 

 Pheasant has from 10 to 14 eggs, the Black-cock from 6 to 

 10, the Grouse 8 to 14, the Partridge 12 to 20, the Quail 

 still more, sometimes reaching two broods of 7 to 12 in each. 

 Here the only exception to the relation between decreasing 

 bulk and increasing number of eggs, occurs in the cases of 

 the Pheasant and the Black-cock; and it is to be remem- 

 bered, in explanation, that the Pheasant is constitutionally 

 adapted to a warmer region, is better fed — often artificially — 

 and leads a less active life. If we pass to domesticated 

 genera of the same order, we meet with parallel differences. 

 From the numbers of eggs laid, little can be inferred; for 

 under the favourable conditions artificially maintained, the 

 laying is carried on indefinitely. But though in the sizes of 

 their broods the Turkey and the Fowl do not greatly differ, 

 the Fowl begins breeding at a much earlier age than the 

 Turkey, and produces broods more frequently: a consider- 

 ably higher rate of multiplication being the result. Now 

 these contrasts among domestic creatures which are similarly 

 conditioned, and closely-allied by constitution, may be 

 held to show, more clearly than most other contrasts, the 

 inverse variation between bulk and sexual genesis; since 

 here the cost of activity is diminished to a comparatively 

 small amount. There is little expenditure in flight — some- 

 times almost none; and the expenditure in walking about 

 is not great: there is more of standing than of actual 

 movement. It is true thai, voung Turkeys commence 

 their existence as larger masses than chickens; but it is 

 tolerably manifest that the total weight of the eggs laid 

 by a Turkey during each season, bears a less ratio to the 

 Turkey's weight, than the total weight of the eggs which a 

 Hen lays during each season, bears to the Hen's weight; 

 and this is the fairest way of making the comparison. The 

 comparison so made shows a greater difference than appears 

 likely to be due to the different costs of locomotion; con- 

 sidering the inertness of the creatures. Eemembering that 



