I 



LIFE HISTORIES OF NORTH AMERICAN DIVING BIRDS. 151 



sprinkled with reddish-brown dots which are thickly concentrated 

 into a dense ring of dark brown and reddish brown dots near the 

 large end. The measurements of 152 eggs, furnished by Mr. Howell, 

 vary in length from 58.5 to 49, in breadth from 38.3 to 33, and aver- 

 age 53.5 by 36 millimeters. 



The period of incubation does not seem to be known, but this duty 

 is evidently performed by both sexes. Mr. Howell (1910) says: 



The old birds not engaged in incubation spend the entire day at sea and are- 

 not to be seen near the islands. These return after dai-k, when their mates 

 leave for the feeding grounds, and in their turns, reseek the burrows just 

 before the first gray lights of morning. 



Young. — When first hatched the young murrelet remains in the 

 nesting site for perhaps two or three days, never more than four daySy 

 according to several good observers. As soon as the young bird is 

 strong enough, perhaps soon after its down is thoroughly dry, it is- 

 conducted by its parents to the water and led away to sea. It seems 

 remarkable that such tender young can stand the buffeting that 

 they must endure in a rough sea and many of them must lose their 

 lives in finding their way through the breakers which surround 

 their rocky birthplace, but perhaps they are safer at sea than on. 

 land. Mr. Howell Avrites me, on this subject, as follows: 



When the eggs are once pipped they show amazing vitality. A set that was 

 rescued by A. van Kossem and me after having been deserted by the parents^ 

 among the cold rocks for 36 hours hatched out two lusty youngsters and these 

 we succeeded in keeping alive for several days on a diet of hardboiled egg. 

 When we substituted bits of fish for this, one died. The other crawled out of the 

 tent, tumbled down a cliff, and when discovered, was making his way out to sea 

 with all speed. They are surely made for swimming for the tarsus when one day- 

 old is equal to that of the adults. When in the downy stage they present the most 

 attractive appearance of any bird that I know and are truly full of life, hop- 

 ping up and down and flapping their little wings from pure joy of life. Upon 

 being placed in the water at the age of two days they at once made themselves 

 thoroughly at home. They c-au then swim as fast as a man usually walks and 

 dive at the slightest suspicion of danger, swimming for several yards beneath 

 the surface. A large fish rose to one of them twice and the little fellow cleverly 

 dodged him. No one as far as I know has ever taken a young hi/poleucus on 

 land that was more than a few days old. Twelve that I kept under observation 

 were taken out to sea before they were 4 days old. H. Wright shot a downy 

 young beside an adult several miles from land, and others have observed them. 

 How they reach the water is a question, for a murrelet's bill is not made to 

 carry anything so bulky and they could not be carried on the. old bird's back. 

 Many must fall a prey to large fish during the first couple of weeks of their 

 life and many more die of exposure during heavy winds. Their down, although, 

 very dense, soon becomes water-soaked and it seems that their only salvation; 

 would be to climb upon their parent's back and dry themselves in the sun. 



Plumages. — The downy young murrelet is thickly and warmly clad 

 in soft down of fine texture, which is particularly dense on the lower 

 parts, so that it is well equipped for swimming at an early age. The 



