THE DEVELOPMENT OF THE SNIPE. 271 



I am unable to bring myself to accept this interpretation. It 

 is clear to me that the two birds are not related except within 

 the common relationship of the Limicolce. The Jack- Snipe is a 

 bird that has adapted itself (unconsciously, of course) to a life in 

 marshes, just as the Ring-Plover has occupied the shingly sea- 

 shore, and the Woodcock the forest. The fortunes of time have 

 preserved its sheltering habitat, but destroyed its enemies, and 

 it is therefore a secure bird. On the other hand, we get the 

 Common Snipe, abundant, increasing, and variable to the verge 

 of caprice. 



I have shown that, although it has invaded the ancestral 

 haunt of the Jack- Snipe, it is not yet quite fitted for its new 

 place, but each favourable variation is used to establish the 

 species, and in time, there is little reason to doubt, it will be as 

 comfortable as its rival. This niche in the scheme of things is 

 a desirable one, for it means security and food throughout the 

 winter. So far this is largely a question of mere observation, 

 but the theoretical aspect is rather interesting. 



It will simplify matters if we assume that all marshes are 

 alike, and assume, too, that the Jack-Snipe has reached its 

 optimum of fitness for life in a marsh. It is rather difficult to 

 imagine any vertebrate reaching the exact optimum of fitness, 

 when not a cell can be changed or altered without a fall in 

 suitability, but, for the sake of the theory, the reader must 

 agree that this bird has done so. He will assume, too, that the 

 Common Snipe is striving also towards the same goal, and then, 

 logically, we must assume that when it reaches the exact optimum 

 of fitness the two birds will be, cell for cell, alike, but unrelated.* 



So much, then, for the theory. Such a state of affairs seems 

 altogether impossible, but really our knowledge is not sufficient 

 to state that it is impossible. Put in other words, it amounts to 

 this : that the place makes the organism from whatever material 

 happens to be on the spot. The marsh, in any country, makes 

 the Snipe. The conditions that in America moulded the Hum- 

 ming Birds from a Coraciiform stock, in the Old World moulded 

 the Sunbirds from the Passerine material most handy. 



* Compare this with the interesting material gathered by Eomanes in 

 support of his theory of " Physiological Selection " — there are no records of 

 hybrids between the Jack and Common Snipe ! 



