PUFFIN. 367 



feet. In this turf are almost innumerable burrows like rabbit-holes ; 

 they extend from three to four feet underground, and often branch out 

 into various passages. At the end of the hole a slight hollow is formed 

 and lined with a little grass or roots, upon which the solitary egg is placed. 

 When first laid, the egg of the Puffin is pale bluish white in ground-colour, 

 very indistinctly spotted and blotched with pale brown and violet-grey. 

 Some eggs are much more finely marked than others, having^ both kinds 

 of spots large and distinct, sometimes confluent and forming an irregular 

 zone round the large end, or elongated into fine scratchy streaks. Most 

 of the markings are underlying ones. The eggs vary in length from 2*6 to 

 2'2 inch, and in breadth from 1'75 to 1'6 inch. It is not easy to confuse 

 the eggs of the Puffin with those of any other British bird ; but some finely 

 marked examples might be mistaken for very poorly marked eggs of the 

 Kittiwake. The egg soon becomes discoloured by contact with the bird's 

 wet feet and the soil of the burrow in which it is laid, and when much 

 incubated is completely coated over with peat. Both birds assist in 

 hatching the egg, and incubation lasts about a month. 



The slightly spotted egg of the Puffin is an exception to the almost 

 universal rule that eggs laid in holes are unspotted white ; but the faint- 

 ness of the spots suggests the idea that the bird has comparatively recently 

 adopted the habit of breeding in a hole, and is consequently gradually 

 losing its power of depositing coloured spots on its eggs. The colour- 

 glands are probably disappearing, according to the well-known law of 

 " degradation from disuse." It can scarcely be supposed that there could 

 be any conscious use on the part of the bird, or effort to use, a colour- 

 gland ; but it may be assumed that the degradation of an organ naturally 

 takes place unless it be kept up to the mark, either by effort to use 

 it, or by the weeding-out by natural selection of those individuals who 

 neglect to do so. 



The young bird remains in the nest for some considerable time after 

 it is hatched, in some cases probably till it is able to fly, and is carefully 

 fed and tended by both its parents. At first the nestling is fed with 

 disgorged fish, but afterwards it eats small fishes as they are brought 

 in by the old birds. The young await their parents' arrival with food 

 at the mouth of the burrow, but if alarmed they hastily retreat into the 

 nest again. As soon as the young are able to get to the sea they 

 never return to the nest, and very soon afterwards the breeding colony 

 is deserted by young and old, who wander far from home in search 

 of the fry on which they largely feed. 



Dixon describes the Puffins on St. Kilda as follows : " St. Kilda is 

 the paradise of Puffins ; every available place is burrowed and honey- 

 combed with their holes, and the sea is often black with the birds. So 

 abundant are they on Doon (an islet of the St. -Kilda group) that there 



