Order LAB1F0BME8 
No. 128. 
Family LABIDJE. 
HYDROPROGNE TSGHEGRAVA STRENUA. 
AUSTRALIAN CASPIAN TERN, 
(Plate 105.)* 
Sylochelidon strbnuus Gould, Proc. Zool. Soc. (Lond.) 1846, p. 21 ; southern coasts 
of Australia. 
Sylochelidon strenuus Gould, Proc. Zool. Soc. (Lond.) 1846, p. 21 ; id., Birds Austr., 
Vol. VII., pi. 22, 1848. 
Sylochelidon strenua Bonaparte, Comptes Rendus Sci., Paris, Vol. XLII., p. 772, 1856. 
Sylochelidon caspia Gould, Handb. Birds Austr., Vol. II., p. 392, 1865 ; Masters, Proc. 
Linn. Soc. N.S.V7., Vol. I., p. 62, 1877 ; Ramsay, ib., p. 386 ; North, Austr. Mus. 
Oat., No. 12, p. 352, 1889. 
Sterna caspia Ramsay, Proc. Linn. Soc. N.S.W., Vol. II., p. 201, 1877 ; id.. Tab. List Austr. 
Birds, p. 23, 1888 ; Wallcer, Ibis 1892, p. 257 ; Mathews, Emu, Vol. X., p. 320, 
1911. 
Hydroprogne caspia Saunders, Oat. Birds Brit. Mus., Vol. XXV., p. 32, 1896 (pars) ; Hall, 
Key Birds Austr., p. 88, 1899 ; Campbell, Nests and Eggs Austr. Birds, Vol. II., 
p. 832, 1901 ; id.. Emu, Vol. III., p. 207, 1904 ; id., ib., Vol. IV., p. 105, 1905 ; 
Hartert, Nov. Zool., Vol. XII., p. 199, 1905 ; HaU, Key Birds Austr., p. 88, 1906 ; 
Mathews, Handl. Birds Austral., p. 20, 1908 ; id., Nov. Zool., Vol. XVII., p. 497, 
1910 ; Littler, Handb. Birds Tasm., p. 146, 1910 ; Ogilvie-Grant, Ibis 1910, p. 185. 
Thalasseus tschegrava strenuus Mathews, Nov. Zool., Vol. XVIII., p. 207, 1912. 
Distribution. South and west Austraha (breeding) ; North and East Australia. 
Adult male in breeding-season. General colour above pale grey, including the back, 
scapulars, wings, and tail ; primary-quills silvery -grey on the outer webs, dark brown 
on the inner edge of the inner webs ; head and nape black, with a short white line 
immediately below the eye ; cheeks, chin, throat and neck all round as well as the 
under surface of body white, like the axillaries and under wing-coverts ; bill red ; 
feet black. Total length 555 mm. ; culmen 77, wing 422, tail 146, tarsus 4’^ 
Adult female. Similar to the adult male. 
Adult in winter. Distinguished from the adult in breeding-plumage by the absence of the 
entire black head, which is represented on the forehead by black feathers with white 
margins, the black increasing in extent on the nape, ear-coverts, and feathers in 
front of the eye. 
* The Plate is lettered Hydro'progne caspia. 
VOL. n. 
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