CH. XXX. PIGEONS — DOVES. 159 



require no little labour to enable them to fill their 

 crops with this small seed. As in this country the 

 turnip fields are for the most part drilled and rolled, 

 the poor birds have the greater diflSculty in satisfying 

 the hunger of their young ones ; and no young bird 

 requires so much food as an unfledged pigeon, in 

 proportion to its size and weight. 



The power of the pigeon to alter the focal length 

 of its eye must be very great, as it is able to see 

 equally well an object at a distance of many miles 

 and a minute seed not more than half an inch from 

 the end of its bill. 



The turtle-dove is sometimes, but only rarely 

 met with as far north as Morayshire, but the 

 stockdove is never seen in that part of the 

 country : if once introduced, I should imagine 

 that it would thrive perfectly well, as both the 

 climate and the natural productions of the district 

 are suited to it. 



The hardy little blue-rock pigeon abounds on 

 all the sea-coast of Scotland, where the rocks are 

 steep and broken into fissures and caverns — one 

 moment dashing into its breeding-place, and rapidly 

 flying out the next ; then, skimming the very surface 

 of the breakers, this little bird gives animation and 

 interest to many a desolate and rugged range of 

 cliffs as far north as Cape Wrath and Whiten 



