14 
allen’s naturalist’s library. 
the others in length. The tarsus is short, being less than the 
middle toe and claw in length, and the tail is very short, being 
less than one-third of the length of the wing. 
I. THE CASPIAN TERN. HYDROPROGNE CASPIA. 
Sterna caspia, Pall. Nov. Comm. Petrop. xiv. i. p. 582, tab. xxii. 
fig. 2 (1770) ; Dresser, B. Eur. viii. p. 289, pi. 584 (1877) ; 
B. O. U. List Brit. B. p. 182 (1883); Saunders, ed. Yarrell’s 
Brit. B. hi. p. 536 (1884); Seebohni, Hist. Brit. B. iii. 
p. 268(1885); Saunders, Man. Brit B. p. 625 (1889); 
Lilford, Col. Fig. Brit. B. part xxviii. (1894). 
Sylochelidon caspia, Macgill. Brit. B. v. p. 626 (1852). 
Hydroproy, 7 ie caspia, Saunders, Cat. B. Brit. Mus. xxv. p. 32 
(1896). 
Adult Male. — General colour above pearly-grey, the rump and 
upper tail-coverts like the back and hardly any paler in tint ; 
wing coverts like the back, the bastard-wing and primary- 
coverts rather paler grey and more frosted in appearance ; 
primaries grey with white shafts, the greater part of the webs 
frosted, the inner web blackish along the inner margin, this 
blackish shade increasing in extent towards the outermost 
primaries, and occupying the entire inner web of the first one ; 
secondaries like the back, with the inner webs slightly more 
dusky-grey ; tail pearly-grey, with white shafts to the feathers, 
the outermost pointed and only slightly exceeding the others 
in length ; crown of head and nape glossy black, the crest not 
elongated ; this black extending below the eyes in a straight 
line from the base of the upper mandible across the lores ; 
remainder of the lores, sides of face, ear-coverts, and a spot 
under the eyes white, like the entire under surface of the body; 
axillaries and under wing-crests white, the inner face of the 
primaries distinctly blackish ; “ bill vermilion-red, sometimes 
horn-coloured at tip ; tarsi and toes black ” {Sautiders). Total 
length, 19 inches; culmen, 2-65 ; wing, 16-5 ; tail, 5-5; tarsus, 
1 - 8 . 
Adult Female.— Not to be distinguished from the male in 
colour, but with a weaker and less brilliantly coloured bill. 
Total length, 19 inches; culmer 2-5; wing, i6-6 ; tail, 6-2; 
tarsus, I '65. 
