AMERICAN OSPREY 361 



which survived. One of our pairs laid sets of four eggs for three 

 years in succession and then laid a set of two. Another pair laid 

 two sets of four, one in 1897 and one in 1902, with normal sets in 

 the intervening years. 



The eggs of the osprey are the handsomest of all the hawks' eggs ; 

 they show considerable variation, and the coloring is very rich; a se- 

 lected series of them is a great addition to an egg collector's cabi- 

 net. I shall never forget my envious enthusiasm when a rival boy 

 collector showed me the first fish hawk's eggs I had ever seen. Nor 

 could I ever forget the peculiar pungent odor that clings to these 

 eggs after many years in the cabinet, a fragrant reminder of many 

 hard climbs. 



The eggs are usually more elongated than other hawks' eggs, but 

 they vary greatly in shape from ovate to short-rounded, elliptical, 

 or elongate-ovate. The shell is fairly smooth and finely granulated. 

 The ground color, which is often largely or wholly concealed, may 

 be white, creamy white, pinkish white, "pale pinkish cinnamon", 

 "fawn color", "light pinkish cinnamon", or "vinaceous-cinnamon". 

 They are usually heavily blotched and spotted with dark rich 

 browns, or bright reddish browns, "bone brown", "liver brown", 

 "bay", "chestnut", "burnt sienna", or various shades of "brownish 

 drab." Rarely they are marked with only the drabs, but often with 

 both browns and drabs. The markings are sometimes concentrated 

 at one end, or they form a ring, leaving much of the ground color 

 exposed. Some are marked like duck hawks' eggs, or caracaras' eggs, 

 and some like red-shouldered hawks' eggs. Very rarely an egg is 

 nearly immaculate. The brighter colors fade with ag-e. 



The measurements of 312 eggs in Mr. McMullen's collection aver- 

 age 61 by 45.6 millimeters; the eggs showing the four extremes meas- 

 ure 68.3 by 50.4, 55.2 by 45.5, and 60 by 41.7 millimeters. In the 

 Bancroft collection there is a longer egg, measuring 69.5 by 48, and 

 a shorter egg, measuring 54.8 by 42.6 millimeters. 



Young. — Incubation, which is apparently performed solely by the 

 female, lasts for about 28 days ; the male feeds the female at the nest 

 while she is incubating, but she sometimes leaves the nest for ex- 

 ercises or to fish for herself. Only one brood is raised in a season, 

 but, if the eggs are taken, a second set will usually, though not al- 

 ways, be laid within three or four weeks. The earliest date on which 

 I have found newly hatched young in Massachusetts is May 25 ; the 

 latest date for unhatched eggs is June 18. The young remain in the 

 nest about eight weeks. I have seen the young leave the nest as 

 early as July 26, but most of them do not leave until the first week 

 in August or later. 



At first the young are very weak and helpless, lying prone in the 

 nest and hardly able to lift up their heads. At this early stage, I 



83561—37 24 



