298 



THE OOLOGIST. 



by oak and hickory saplings with here 

 and there a small pine shrub, the whole 

 forming a perfect paradise for the 

 Prairies, whose queer little wiry notes 

 could constantly be heard. These notes 

 are quite characteristic and easily re- 

 cognized and are apt to be the only clue 

 <to the auther's whereabouts, for discolor 

 evidently has no wish to be "seen and 

 not heard," but quite the reverse. 



In their choice of nesting sites they 

 again show little diversity, for with few 

 •exceptions the nests are built within 

 five or six feet of the ground, usually in 

 an upright crotch of three branches 

 rather than two. One nest, the first 

 found, was within one foot and a half 

 of the ground. I may mention here, 

 however, a case coming under my ob- 

 servation in north-eastern Pennsylvania 

 which is quite exceptional so far as my 

 experience runs, namely a [nest of this 

 species in the very tip top of a maple, 

 at least fifty feet high. It was quite in- 

 visible from the ground and was only 

 discovered by chance during an unsuc- 

 cesful prey upon a pair of Hummers, 

 whose bunch of lichen, alas, was unas- 

 sailable by anything short of wings. 



Although in the locality referred to 

 above most of our specimens were tak- 

 en in the hardwood saplings, a large 

 proportion of the scattering pines also 

 held nests. 



While as has been mentioned the 

 birds are usually shy and retiring, they 

 are fearless enough when the nest is 

 once obviously discovered, and once 

 they decide upon a nesting site they 

 cling to it with great attachment, for 

 though we frequently disturbed them 

 while building or flured them from in- 

 complete sets in no instance did the 

 parents abandon nest or eggs as so fre- 

 quently happens with some species. 



The nests themselves are quite firm 

 and compact but hardly so neatly put 

 together as one would expect from such 

 trim little housekeepers, and usually 

 there was little trouble in distinguish- 



ing them from those of the Summer 

 Yellow Bird, which also nested abund- 

 antly. 



The number of eggs was four ex- 

 cept two sets of three, no nest holding 

 five though according to most collectors 

 this is not uncommon. 



As last season I had no opportunity 

 to visit my Prairies, next year I will 

 pay them special attention to attone for 

 my apparent neglect. 



Migration. 



The so called migratory instinct in 

 birds has occasioned much speculation 

 amoug thoughtful persons. A great 

 deal has been written on this subject, 

 but the basis of truth, I believe, has not, 

 as yet, been satisfactorily reached. It 

 is a remarkable and a well established 

 fact that certain birds journey from 

 one locality to another at particular sea- 

 sons of the year and also that a period- 

 icity of motion is observed. In fact, 

 custom has made this periodical return 

 of the birds of passage to there old 

 haunts so certain that ornithologists are 

 able to forecast, within a few days, the 

 time such and such birds are to arrive. 

 Further that the motion of many of the 

 migratoiy birds is augmented or re- 

 tarded, according to circumstances, by 

 meteorological changes, has been sub- 

 stantially corroborated. That knowl- 

 edge and reason are used by the birds 

 during their migrations is very evident, 

 but it has been found necessary, as a 

 rule, to revert to instinct to account for 

 the fundimental impetus which governs 

 their seasonal movement. 



When we observe or learn of the 

 movements of the Bald Eagle, the Os- 

 prey or any of the other large birds 

 which habitually frequent the sea-coast 

 or large water courses we do not won- 

 der that they are able to winter in a 

 semi-tropical clime and to return to 

 their old breeding places in the spring. 

 These birds can easily follow the sea- 



