854 



U. S. p. R. R. EXP AND SURVEYS — ZOOLOGY — GENERAL REPORT 



STEENA FRENATA, Gambel. 



TUc Least Tern. 



Sterna minuta, Wii.s. Am. Orn. VII, 1813, 80 ; pi. Ix.— Bonap. Syn. 1828, No. 288.— Aim. Orn Biog. IV, 1838, 



175 — Ib. Birds Am. VII, 1844, 119 ; pi. ccccxxxix. 

 Slerna argentea, Nutt. Man. II, 1834, 2S0. 

 Sterna frenata, Gamb. Proc. Acad. Sci. Phil. IV, 1848, 128. 



Sp. Ch.— Adult. On the forehead is a triangular white spot extending to the eye ; crown, occiput, and a lino from the eye to 

 the upper mandiljle, deep black ; entire upper plumage and wings clear bluish gray ; first two primaries, with the outer web 

 and half the inner next the shaft, grayish black, ends of the same color, inner margins white, the shafts of these two quills are 

 black ; the other primaries same color as the back, with the inner margins white ; tail same color as the back except the outer 

 margin of the exterior feather, and the inner webs of the others at the base, where they are white ; entire under pluaiage 

 silvery white ; bill pale orange yellow ; iris hazel ; legs and feet light orange red. 



Length, 8J inches ; wing, 6| ; tail, 3, ; bill, 1^ ; tarsus, 9-lG. 



TIab. — Texas to Labrador ; western rivers. 



Four specimens in the collection. 



List of specimens. 



HYDROCHELIDON, Boie. 



Hydrochelidon, Boie, Isis, 1822, 563. 



Ch. — Bill rather short, strong, the upper mandible curving slightly to the tip ; nostrils basal, lateral, and longitudinal, the 

 frontal feathers reaching nearly to the opening ; wings very long and pointed ; tail moderate and emarginate ; legs short ; the 

 anterior toes slender, with the webs deeply indented ; hind toe small ; claws slender and acute. 



We have but a single species to represent this genus, which much resembles and is very 

 clo.selj allied to the European ^S*. nigra. 



They frequent the salt water bays as well as the inland rivers and lakes. Late in the 

 summer I have noticed them in compact flocks flying rapidly forward in the manner of some 

 species of Tringa. 



HYDROCHELIDON PLUMBEA, (Wilson.) 



Tbe Sliort-talled Tern. 



Sterna i>lv,mbea, Wils. Am. Orn. VII, 1813, 83 ; pi. Ix. (Young.) 



Sternanisra, Eonap. Syn. 1828, No. 289.— Sw. & Rich. F. B. A. 11, 1831, 415.— Ndtt. Man. II, 1834, 282.— 



AuD. Orn. Biog. Ill, 1835, 535 : V, 1839, G42.— Ib. Birds Am. VII, 1844, IIG ; pi. cccc.\.\xviii . 

 " Sterna aurinamensis, Gm." — Bonap. Cons. Gav. Syst. Comp. Rend. XLI, 1855. 



Sp. Ch. — Jldull. Head, neck, breast, sides and abdomen, black ; lower tail coverts white ; under covering of wings ashy 

 gray ; back and wings dark plumbeous gray ; the first four primaries grayish black, with their shafts white ; bend of the wing 

 edged with wliite ; tail same color as the back ; bill brownish black ; iris brown ; legs and feet reddish brown. 



Length, 9j inches; wing, 8j ; tail, 3, ; l)ill, 1 J ; tarsus, |. 



Young. Back, wings and tail, light i)lumbeous, with the feathers of the back margined with brown; top of the head and 

 around the eyes brownish black ; front and under plumage white ; tail short and but slightly forked. 



Hah. — Texas to the New England States, Mississippi river and tributaries, fur countries. 



There are several tine specimens in the collection. 



