.IriA 1891.] 



AND OOLOGIST. 



105 



The Coloration of Eggs. 



Mr. J. Parker Norris' statement of his belief 

 tliat successive sets of eggs from the same 

 pair of birds bear a strong resemblance to each 

 other in shape, size and coloration was read 

 by me with great interest. I can jirove this to 

 be a fact in some cases, and believe that when 

 properly investigated it will prove a general 

 law. 



The best confirmation of this I know of is in 

 the case of the Golden Eagle, which uses tlie 

 same nest year after year. After collecting 

 the eggs of some half dozen pairs for several 

 years I have learned to know the eggs of each 

 individual as well as I know the appearance of 

 my neighbor's dog. The eggs of one partic- 

 ular pair of eagles are always very large, 

 delicalely and beautifully maiked, and are 

 looked for anxiously the first thing, as an 

 especially fine prize. I believe that if shown 

 to-day the eggs of at least three pairs of eagles 

 I know in Santa Clara County I could witliout 

 hesitation describe the locaticm of the nest of 

 each set. 



It is a fact of wonderful interest if, as seems 

 the case, the rule is a general one, and each of 

 the eggs of the (iuilleinot, so marvellously 

 diverse in ni.nrkings, are duplicated in the eggs 

 sub.sequently laid by the same bird. This will 

 not be hard to find out. When I next go to 

 the Farallones I think I will catch a Guillemot 

 and make it lay. Tlarri/ B. Taylor. 



.\Lim«(ta, Cal. 



This is tlie first set that has, to my knowl- 

 edge, been taken in this county for many 

 years. //. b. Hurd. 



Minneapnlis, Minn. 



[This was very poor "identification." — J. 

 P. N.] 



Swainson's Hawk in Minnesota. 



Last week a boy called at my liouse with the 

 information that he liad that afternoon taken 

 a set of four eggs from a Broad-winged Hawk's 

 nest. Thinking that he liad made a mistake 

 in the identity of tlie bird, as a set of four 

 eggs from a Broad-winged Hawk's nest is 

 very uncommon, I askc^d for a description of 

 the bird. But what was my surprise when lie 

 described veiy minutely a Swainson's Hawk. 

 Saying nothing to arouse his curiosity I placed 

 before him a series of sets of Hawks' eggs, 

 and asked him to pick out as near as possible 

 one that would comjiare with tlioso he had 

 found. And without the least hesitation he 

 picked up an egg of the Swainson's Hawk. 



This was certainly enough to prove their 

 identification. Since that time I have exam- 

 ini'd them, and they are witliout a doulit the 

 eggs of the Swainson's Hawk. 



Large Set of Grouse Eggs. 



While walking through the woods on May 

 21, 1891, I flushed a Ruffed Grouse, and on 

 going to the spot was somewhat surprised to 

 find a set of twenty-one eggs. The nest was 

 on the ground and composed of oak leaves. 

 The eggs were light brown, and (juite a 

 number of them were .spotted. I left them as 

 this bird is nearly exterminated around here 

 now, and if they will breed I think it best to 

 let them. Is not this a large set, and could it 

 have been a double one? Davie gives the set 

 as from six to fifteen; Samuels as six to 

 thirteen. I should like to hear from others 

 about this. F. A. Jirnvm. 



Heverly, Mass. 



Measuring Heights Again. 



The following method of measuring the 

 height of trees and other inaccessible objects 

 gives greater accuracy than any I know of, 

 where no instruments are used. It has, how- 

 ever, tlie disadvantage of being available only 

 when old Sol will lend his assistance. This 

 cimdition being given, however, every collector 

 will agree with me that the required apparatus, 

 which is his shadow, is the lightest part of his 

 outfit. The collector's shadow is ai)plied to 

 that of the tree as a measuring rod. The num- 

 ber representing their ratio multiplied by the 

 height of the collector gives the height of the 

 tree. It is important that the point measured 

 from on the giound should be directly under 

 the point whose height is to be measured. In 

 the case of projecting limbs or leaning trees 

 this point, of course, has to be estimated. 

 Ine<iualities of the ground will not interfere 

 with this kind of measuring, since both 

 shadows are affected similarly. Where the 

 foliage is too dense to allow the casting of the 

 collector's shadow it may be measured and 

 applied to that of the tree by means of an 

 extonipori zed measuring-rod. 



The jirinciple on which this metliod depends 

 is the familiar one that two c(iual angled tri- 

 angles have their sides proportional. The two 



