





NATATORES. 







/ 



Ho 









Dimensions 

















Of the mature bird. 













Inch. 



Lin. 



Inch. 



Lin. 





Inch. 



Lin. 



Length, total 



15 







L ength of bill to rictus . 1 



9 



Length of inner toe 







41 



„ of tail 



6 



10 



„ of tarsus . . 



7 



„ of hind toe . 



. 



H 



„ of wing 



. 10 



6 



„ of middle toe . 



7 



„ of hind nail 







Of 



,, of bill above . 



1 



2 



„ of middle nail . 



H 





— R. 





[180.] 3. Sterna nigra. (Linn.) Black Tern. 



Genus, Sterna, Linn. 



Black Tern. Penn. Arct. Zool, ii., p. 525, No. 450. 



Hirondelle de mer epouvantail (Sterna nigra). Temm., ii., p. 749. 



Sterna nigra (Black Tern). Sab., Frankl. Journ., p. 695. Bonap. Syn., No. 289. 



This Tern is common in the interior of the fur countries on the borders of the 

 lakes. It breeds in the swamps, and feeds chiefly on winged insects. 



DESCRIPTION 

 Of a male, killed on the Saskatchewan, June 17, 1827. 



Colour. — Head and nape velvet-black. Neck and whole under plumage to the vent 

 black. Bach blackish-grey, passing on the rump, tail, and wings, to pale bluish-grey. 

 Outer web of the first quill and inner webs of the others blackish-grey ; their shafts brownish- 

 white. Outer tail feather narrowly edged exteriorly with white. Vent and under tail coverts 

 pure white. Bill pitch black. Feet blackish-brown. 



Form. — Bill smaller than that of the Arctic Tern, but similar in shape. Wings an inch 

 and a half longer than the tail. Tail short, comparatively slightly forked ; outer feathers 

 three-quarters of an inch longer than the central pair. Thighs bare for four lines. Tarsi 

 shorter in proportion than those of St. arctica. The webs are abbreviated in their middles, 

 the outer one being only 4| lines deep, and the inner one 3^- lines *. 



Dimensions. 



Inch. Lin. Inch. Lin. Inch. Lin. 



Length, total . .11 Length of bill to rictus . 1 4£ Length of inner toe . . 5 



„ of tail . . .34 „ of tarsus ..07 „ of hind toe . 2i 



„ of wing ..83 „ of middle toe .07 „ of hind nail . . lj 



„ of bill above .13 „ of middle nail . 7 — R. 



* A specimen in mature plumage, killed in Lincolnshire, differs merely in the black being less deep on the under 

 plumage, and rather less extended on the upper. Form and dimensions the same. — Wilson's Sterna plumbea (pi. 60, 

 f. 3) corresponds in description with the yearling birds of St. nigra, though the figure is not well coloured. It is sin- 

 gular that the thirty specimens which that author killed should all have been young birds. — R. 



