THE OSPREY. 



Crow or other animal passing overhead and the 

 safety of the nest be assured. In only one of 

 these nests was there any possibility of mimicry 

 as seen from below or sidewise. number four 

 being the only one having lichens anywhere on 

 the tree, except on the nest. 



The female sits on the nest at right angles to 

 the direction of the branches, and thus probably 

 feels safer in having an umbrella over her dur- 

 ing her nesting labors, and can the more readily 

 slip out of the nest when necessary. 



We have in the Blue-gray Gnatcher a delicate 

 little bird small of body, and with long plumage. 

 It builds a nest constructed as well as possible 

 to retain the heat of the sitting bird, but even 

 this is probably not enough to ensure the hatch- 

 ing of the eggs, so the species has apparently 

 adopted two other means to assist in incubating, 

 one of which is common to many birds. 



If we make a composite photograph of the 

 sites of these five nests and compare it with 

 the points of the compass we shall find that 

 what at first sight looks like chance location 

 as regards direction assumes a possibly inten- 

 tional selection on the part of the birds of a site 

 with reference to the sun's rays during the early 

 or greater part of the day. These were so placed 

 as to receive the earliest sunlight; possibly on 

 the other side of the river an opposite direction 

 might have been adopted. 



It should also be borne in mind that these 

 nests are not so placed on trees that they are 

 protected from the sun by a thick canopy of 

 leaves. During the first half of May when these 

 birds are nesting there are in such localities no 

 leaves to speak of, and two of the nests, num- 

 bers two and four being on dead- trees could 

 have no leaves over them. The lichens proba- 

 bly serve the purpose of retaining! at night a 

 portion of the heat received during the day or 

 at least of preventing its rapid radiation, and 

 may also serve to prevent the escape into space 

 of the birds, own warmth. 



Another point in the nesting economy of this 

 species is that the female rarely leaves the nest, 

 but is fed by the male. She invariably rewards 

 him for such service with a simple, quaint song 

 which was the means of my finding the last two 

 nests. 



The nest shown in the picture was number 4. 

 It is the finest piece of bird architecture that I 

 have seen, and is now on exhibition in the col- 

 lection of the National Museum. In regularity 

 and neatness of structure it is perfect and can- 

 not be excelled. It measures 2-,',. inches in 

 diameter, is 2-,^ deep: the opening-is 1 ' 4 inches 

 across while the cavity is 1 ' 2 inches deep. The 

 diameter of the cavity is much greater, possibly 

 an inch, than the opening. 



TENANTS OF UNCLE SAM. 

 By Paul Bartsch, Washington, D. C. 



No place about Washington offers greater 

 charms and opportunity to the bird-lover than 

 the government reserve known as Rock Creek 

 Hark. Particularly attractive at this season is 

 the region which conies more directly under the 

 control of the Zoological Park. Its easy access. 

 its splendid roads and paths, and romantic, rug- 

 ged surroundings all conspire to make it the 

 favorite haunt of every one, while the protection 

 afforded to bird and beast within this area has 

 gained for it a fauna scarce to be rivaled any- 

 where. 



The part of the /Coo which has held our at- 

 tention mostly, is the region from the high 

 bridge which spans the creek at Cincinnati 

 street to the rustic wagon bridge, and from the 

 east fence to the western slope — an area not more 

 than a fourth of a square mile in extent. But 

 within this area we have land of various altitudes 

 ranging from water level to the hill tops of a 

 hundred and fifty-five feet elevation. 



A broad well-kept macadamized road winds 

 its way down from the southeast gate to the 

 waters' edge, where it branches, and one part 

 turns back, southward, crossing the creek by a 

 ford, while the main portion passes to the north 

 and spans the stream with a rustic bridge a 

 little beyond its first bend, then follows it more 

 or less, in its sinuous curves. 



Just below where the ford crosses our stream 

 a series of stepping stones enable the traveler 

 on foot to reach the opposite bank, from where a 

 woody winding path, a splendid "birdy place," 

 will lead him about the base of the western hill 

 to the farther end of the rustic bridge. Still 



another path with broad boarded walk trends 

 northward, immediately after one enters the 

 southeast gate and takes one, by a short cut. 

 down many a step to the animals and the sicmd 

 wagon bridge. 



The entire area under discussion, excepting- 

 the lawn which follows the road from its fork to 

 the rustic bridge, and the immediate region about 

 the gate, -is well wooded— every effort having 

 been made to leave undisturbed all the natural 

 features which the ground presented; that 

 birds, beasts and plants might flourish without 

 the sad influence of all-civilizing man. 



We made many an early morning excursion to 

 this field in early spring, and watched the birds 

 returning one by one, some to stay while others 

 rested but for a brief period, then continued 

 their journey to the north, whither fond hopes 

 of a happy home irresistibly drew them. 



Midst all this bustle and commotion some of 

 our summer residents settled down to household 

 duties, and long before the last Black-poll 

 Warbler had left our terrain Phoebe's young 

 had learned their first lesson on the wing-. 



< in the ninth of May a member of my class 

 pointed out the first Blue- Grey Gnatcatcher's 

 nest for this season. It was situated in the 

 large birch, at the waters edge, perhaps a 

 hundred yards north of the stepping stones, on 

 the left bank of the creek. The site selected 

 was a charming one, commanding a view of the 

 stream as well as the road with its bordering 

 lawn. The nest seemed incomplete, that is. not 

 a bit of the usual lichen ornamentation had been 

 bestowed upon it. and both birds were whisking 



