THE BLACK TERN. 755 



is probable that the niigratury ninxenient is rather compact, and that the birds 

 do not always come closer than the outer coast. 



A most interesting fact in connection with the life history of this species 

 has recently come to liglit. While the bird breeds in the northern portions of 

 tlie northern hemisphere, it summers ( i. e. Antarctically speaking) chiefly 

 within the Antarctic Circle. In it, theref(Tre, the migratory instinct is more 

 highly developed tlian in an}' other creature, and it is the only bird which, in- 

 dividually as well as aenerically, nia\' ha\e distanced both Peary and Gleason. 



No. 303. 



BLACK TERN. 



A. O. U. Xo. //. Hydrochelidon nigra siirinamensis ((lUicl.). 



Description. — Adult in sitiiiincr: Head and neck all anuind, ami iuider])arts 

 sooty black : the crissum white, and the edges and lining of wings white or pale 

 pearl gray: underparts plumbeous, darker on upper back, where it lilends thru 

 slate with black cervix ; jirimaries not different on exposed webs, the inner webs, 

 however, dusky, lightening on the inner half, and the shafts white: tail slightly 

 forked : bill and feet black-. , /</;/// /;; i^'iiitcr: Lighter, the black replaced bv white, 

 save on back of liead, or])its, and auriculars, where obsciu-ely persistent: upper- 

 parts deep pearl gray. I iiiiuaturc : Like adult in winter, but uppcrparts nmrc 

 or less tinged and tipped with brownish, and sides washed with gra\ ish. Length 

 9.00-10.25 (228.6-260.41 : wing S.oo (203.2) ; tail 3.00 (76.2) : bill i .o_| 1261.4) : 

 tarsus .67 ( 17 ). 



Recognition Marks. — Chewink tn Rubin size. l.>ut appearing abdut Killdeei 

 size: sooty black and plumbeous coloratiim distinctive in Ijreeding ]iluniage : dark 

 pearly gra\' of upperparts with black l)ill (and feet), with small size sufficiently 

 distinctive at other seasons. 



Nesting. — Xcst: in marshes, on the ground, cir on broken-down reeds, old 

 Grebe nests, old musk-rat houses, and the like. Ei/gs:. 2 or 3, sometimes 4, gray- 

 ish olive, or pale liniwnish, heavily spotted and lilotched with blackisli brown, the 

 markings sometimes confluent at larger end. Av. size. 1.35 x .08 (34.3x24.9). 

 Season: c. June 10; one brood. 



General Range. — Temperate and tropical America. From Alaska and the 

 Fur Countries to Pirazil, breeding from the middle Ignited States, west of the 

 AUeghanies northward. 



Range in Washington. — Cmnmon summer resident in marshes on the larger 

 lakes of the East-side: casual on l\iget Sound fone record: -Vug. 26, 1899. 

 Nooksack Marsh, near Bellingham, by J. M. Edson). 



Authorities.— ["Black tern." Johnson. Rep. Gov. ^^■. T. 1884 (1885), 23.] 

 Johnson ( Roswell H.). Condor. \'ol. A'lH. Jan. 1906. p. 27. T. E. 

 Specimens. — U. of W. P. Prov. E. 



