THE COMMON TERN. 559 



No. 269. 



COMMON TERN. 



A. O. U. No. 70. Sterna hirundo (Linn.). 



Synonyms. — Wilson's Tern ; Sea Swallow ; "Bass-gull." 



Description. — Adult, in summer: Top of head and nape uniform deep 

 black ; back and wings pearl-gray ; wing-quills dusky, more or less silvered over, 

 except on outer web of outer primary ; the inner half of inner webs sharply 

 white, but not reaching tip; rump, upper tail-coverts and tail (basally and cen- 

 trally), white; tail deeply forked, the outer pair of feathers elongated and nar- 

 rowly tapering but not, or barely, reaching the tips of closed wings; their outer 

 webs abruptly grayish-idtisky, contrasting with white of inner webs; the succeed- 

 ing pair also similarly marked; under parts white, tinged, except on throat and 

 crissum, with pale pearl-gray or lavender-gray; bill vermilion-red, blackening 

 on tip; feet orange-vermilion. Adiilt, in winter: Similar, but black cap im- 

 perfect, restricted to hinder portion of head, or merely indicated ( ?) ; under 

 parts pure white; bill and feet not so bright. Young (in August) : Forehead 

 and lores ashy-gray ; region about eyes, hind crown, and nape leaden black ; back, 

 scapulars and wings pearl-gray, each feather tipped with brownish-buff and mingled 

 subterminally with brownish-dusky, forming a strong bar; upper tail-coverts and 

 tail lighter pearl-gray, the central feathers of the latter tipped with buffy; the 

 anterior lesser wing-coverts bluish-dusky, with narrow ashy edgings; edge of 

 wing and quills plumbeous-gray; under parts, white. Length, 13.00-16.00 

 (330:2-406.4) ; wing 10.25 (260.4) ; tail 5.00-6.00 (127.-152.4) ; bill 1.38 (35.1) ; 

 tarsus .80 (20.3). 



Recognition Marks. — Little Hawk or Crow size ; black cap ; pearl-gray 

 mantle ; deeply forked tail ; extensive white, or pale grayish plumage ; graceful 

 flight; lake- (rarely river-) haunting habits. Known from the preceding species 

 by outer pair of tail-feathers dark on the outer instead of the inner web; under- 

 parts not pure white in breeding season. Distinguishable at a glance from S. 

 dougalli by bill extensively vermilion. 



Nests, in colonies, on beach shingle, or in grass of low islands, lined or not, 

 with bits of bark, grass, etc. Eggs, 2 or 3, rarely 4, very variable in ground color 

 r — light bluish or greenish, dull white, stone, light-olive, etc., spotted and blotched 

 heavily, or not, with blackish-brown or chocolate, and with lavender shell-marks. 

 Av. size, 1.60 x 1.20 (40.6 x 30.5). 



General Range. — -Greater part of the northern hemisphere and Africa. 

 In North America, chiefly east of the Plains, breeding from the Arctic Coast, 

 somewhat irregularly, to Florida, Texas, and Arizona, and wintering northward 

 to Virginia. Also coast of Lower California. Appallingly reduced in numbers 

 on Atlantic seaboard within recent years. 



Range in Ohio. — Spring and fall migrant, not common except on Lake 

 Erie, where it breeds sparingly. 



WHAT a piece of vi^ork is a Tern! how gentle in instinct! how un- 

 trammelled in. discursion ! in form and moving how elegant and admirable! in 

 action how like the swallow ! in innocence how like the dove ! the beauty of the 

 air ! the paragon of sea-birds ! 



