6. STERNA. 99 



ii. p. .307 (1884) ; Turner, Rep. Alaska, p. 127 (1886) ; A. O. U. 

 Check-l. N. Amer. B. p. 94 (1886); Ridgio. Man. N. Amer. B. 

 p. 45 (1887) ; Ndmn, Rep. Alaska, p. 60 (1887) ; Seebohm, B. Japan. 

 Emp. p. 299 (1890 : Inuboye) ; Allen, Auk, 1893, p. 123. _ _ 

 Sterna camtschatica, "Pallas,''^ Finsch, Ahh. nat. Ver. Brem. 'in. p. 85 

 (1882: nee Pallas). 



Adult in hreedincj-plumaiie. Centre of forehead and backwards to 

 the eye white ; below, a black loral streak from the maxilla to the 

 eye; crown and nape black; mantle slate-grey, the secondaries edged 

 with white ; primaries darker grey, the outer web of the first 

 blackish, shafts white, a dark line next the shaft on each inside web 

 and running up the inner margin, white wedges to the four outer 

 primaries ; rump and tail pure white, streamers long and pointed ; 

 under tail- and under wing-coverts white ; abdomen and breast 

 pale slate-grey ; chin and lower cheeks white : bill and feet black. 

 Total length 13-5 inches, culmen 1-6, wing 10-75, tail 6'5 to 7, 

 depth of fork 3"5-4, tarsus 0-75, middle toe with claw 1. The 

 sexes appear to be alike in plumage. 



Adult in winter. Similar to the above, with rather more white on 

 the forehead. 



Immature, unknown to me. In a s])ecimen obtained on August 

 23rd, 1879, a few sandy-white margins to the tips of some of the 

 feathers of the mantle can be detected, and the general plumage 

 is dull ; otherwise the bird is like an adult, with well-developed, 

 though abraded, streamers ; the lower mandible slightly reddish 

 at the base. 



Young (Sept. 1). Forehead and crown brown, with blackish 

 streaks, which become confluent on the nape ; feathers of the 

 mantle chiefly black, deeply edged mth rufous buff, flight-feathers 

 dark grey ; rump and tail grey, the outer webs of the exterior pair 

 of rectrices white, all the feathers tipped with buff ; underparts dull 

 white, with some clove-brown on the upper breast and sides of the 

 neck : bill and feet ochre-yeUow. 



Nestling (No. 97160, St. Michael's, Alaska, July 29th, 1880; 

 E. W. Nelson). " Above rather light sooty brown, confusedly 

 marbled or mottled with dusky, the head with the light brown pre- 

 dominating, and the dusky markings more distinct. Forehead, 

 chin, entire throat, and sides of the neck uniform sooty slate ; 

 jugulum and breast pure white ; sides, flanks, abdomen, and anal 

 region sooty grey. liill pale yellowish brown (flesh-colour in life), 

 with black tip; legs and feet pale yellowish brown (flesh-colour in 

 life?)" (Waler-B. N. Amer. ii. p. 307). Mr. Nelson goes on to 

 describe No. 97162, which is now in the B.M. coll., and shows the 

 points in which it diff'ers from the above. The specimen in question 

 has been labelled " *S'. macrura " and subsequently " S. aJeutica ?"; 

 and it is exactly like downy nestlings of the Arctic Tern from 

 Europe and from St. iLichaers, Alaska. There is also in the British 

 Museum a nestling obtained by Mr. C. Drexler on St. Paul's I., 

 July 2oth, which agrees better with Mr. Nelson's description, while 

 it is unlike the nestling of an Arctic Tern, or indeed any other 



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