COMPETITION BETWEEN GUILLEMOTS 193 



vigilant in resisting - intrusion upon its few 

 square feet as the Bunting is in guarding its 

 many square yards, so that the evidence seems 

 to show that that part of the inherited nature 

 which is the basis of the territory is much 

 the same in both species. What we have then 

 to consider is, What is the biological value to 

 the Guillemot of an inherited nature which, 

 for the Bunting, has utility in relation to the 

 supply of food for the young ? Up to a point, 

 the act of securing a territory has like value 

 for each respective species, whether the area 

 occupied be la~rge or small — that is to say, it 

 enables the one sex to discover the other with 

 reasonable promptitude. 



For the greater part of the year. Guillemots 

 live at sea ; singly, in twos or threes, or in 

 small parties, they move upon the face of the 

 waters, extending their wanderings far away 

 from land, out into the broad ocean, where 

 for weeks together they face the gales and 

 heavy seas of the Atlantic. But in due course 

 and in response to, internal organic changes, 

 they return, like the Warbler, to their breeding 

 grounds— rocky headlands or islands appropri- 

 ately situated and affording the appropriate 

 rock formation. During all these months of 

 wandering, the majority seem to ignore the 

 land, to pass away from it altogether, and to 

 spread themselves over the surface of the ocean 

 regardless of mainland or island. Some useful 

 observations, which throw some light on the 

 distance that Guillemots are accustomed to 



