KIOHAKDSU^S'S OWL. 349 



Tliree of the eggs referred to by Mr. Nelson are now in the U. S. National 

 Museum collection, and measure, respectively, 31) by 32.5, 39 by 31.5, and 

 38.5 by 32.5 millimetres. 



The eggs of the Old World form, Nydalc tcngmalmi, a species closely 

 related to Richardson's Owl, but a trifle lighter colored, and which, like the 

 Lapp and Hawk Owls, is also likely to occur in Alaska, measure, according 

 to Seebohm, from 31.7 to 33 millimetres in length and from 26.6 to 27.9 

 millimetres in breadth. Tiiere should be little or no difference in the rela- 

 tive size of the eggs of these birds. Like ours, Tengmahn's Owl is prin- 

 cipally confined to timbered regions, and is said to nest in natural hollows 

 of trees or tlie excavations of the Black Woodpecker. 



The information obtained by Dall from Indians, whose testimony is not 

 usually very reliable, is in this instance probably entirely correct, and I 

 think if, as Mr. B. R. Ross states, this Owl nests in trees "that is, in an 

 open nest," it will be found the exception and not the rule. 



Tlie only genuine eggs of Richardson's Owl in the U. S. National 

 Museum collection are three collected l»y Mr. Ross, at Fort Simpson on the 

 Mackenzie River, in latitude 62° N., on May 4, 1861. As there appear to 

 be no memoranda showing the exact manner in which these eggs were 

 obtained by him, it is likely that they were either taken from a cavity in, 

 or from an open nest on, a tree. 



The eggs described by Mr. Nelson, and previously referred to, are unques- 

 tionably those of the American Hawk Owl; they are absolutely indistinguish- 

 able and altogether too large for the s])ecies under consideration. How close 

 they come to the eggs of the former will be seen by a compai'ison of the aver- 

 age measurement of thirty-two specimens now in the U. S. National Museum 

 collection, which is 39.5 by 31.5 millimetres. 



Seebohm, in speaking of Tengmahn's Owl, says: "This bird is a very 

 early breeder, and even in latitude 67^"' N., Wheelwright's eggs were all 

 taken between the 2d and 13th of May; whilst at Muoniovara, a degi'ee still 

 farther to the north, Wolley obtained eggs lietween the 18th of May and 

 2d of June, and received them from a little farther north between the 1st 

 and 27th of June. Wheelwright describes its call note as a very musical 

 soft whistle, never heard except in the evening and at night. Its food con- 

 sists of mice, beetles, and small birds." ^ 



Like the preceding, Richardson's Owl is an early breeder and nests 

 probaljly at about the same time in corresponding latitudes. The number of 

 eggs laid is likely the same, from three to seven. These are pure white in 

 color, oval in shape; tlie shell is smooth, close grained, and shows but little 

 luster. 



The three specimens in the U. S. National Museum collection measiu-e, 

 respectively, 33 by 27.5, 32 by 27.5, and 31 by 27 millimetres. 



The type, No. 5098 (PI. 12, Fig. 6), is one of the above mentioned 

 specimens. 



' History of British Birds, Seeboljtn, 1883, Vol. I, pp. 164, 165. 



