Order LARIFORMES. 
No. 13. 
Family LARIDJE. 
LEUCANOUS ALBUS. 
(royanus.) 
WHITE TERN. 
Leucanous Mathews, Birds Austr., Vol. II., pt. iv., p. 432, Nov. 1st, 1912. Type (by original 
designation): Gygis rnicrorhynchus Saunders. 
Gygis Wagler, Isis, Nov. 1832, heft. XI., col. 1223. Type (by monotypy) : Sterna Candida Gmelin. 
Not Gyges Bory St. Vincent, Ency. Meth., p. 449, 1825. 
Alphagyis Mathews, Austral. Av. Bee., Vol. II., pt. v., p. 110, Sept. 24th, 1914, new name for 
Gygis Wagler. 
Sterna alba Sparrman, Mus. Carlson., fasc. 1, No. ii., 1786: restricted to Ascension Island. 
Gygis alba royana Mathews, Birds Austr., Vol. II., pt. iv., p. 433, pi. 119, Nov. 1st, 1912: Kermadec 
Island; id., List Birds Austr., p. 51, Dec. 1913. 
Gygis Candida Gould, Birds Austr., pt. xxxv., Vol. VII., pi. 30, Dec. 1st, 1848 ; id., Handb. Birds 
Austr., Vol. II., p. 405, Dec. 1865; Saunders, Cat. Birds Brit. Mus., Vol. XXV., p. 149, 
1896 (pref. Nov. 3rd, 1895). 
Gygis alba Hartert, Nov. Zool., Vol. V., p. 67, 1898 ; Mathews, Handb. Birds Austral., p. 22, 
Jan. 1908. 
Gygis alba Candida Mathews, Nov. Zool., Vol. XVIII., p. 211, Jan. 1912. 
Leucanous albus Mathews and Iredale, Austral. Av. Rec., Vol. IV., p. 110, Dec. 16tli, 1920 ; id., 
Manual Birds Austr., p. 105, March 9th, 1921. 
Leucanous albus royanus Mathews, Syst. Av. Australas., p. 142, 1927. 
Distribution. Norfolk Island: Kermadec Island, East coast of Australia ? 
Adult male. Entirely ivory-white ; short feathers surrounding the eye black ; shaft-lines of 
primary-quills dark brown, somewhat darker and inclining to black on the shafts of the 
tail-feathers ; bill black at tip, base blue ; iris brown ; tarsus, toes and webs yellow. 
Total length 330 mm.: culmen 45, wing 250, tail 110, tarsus 16. 
Adult female. Similar hut smaller. 
Immature (half grown). Down mottled, not uniform ; a large black patch above and extending 
behind the eye; pale brown line above, and then black markings towards the nape; 
greyish-brown on the fore-head with lighter edge; back dark brownish-grey with 
indistinct pale blotches ; wings similar ; throat dark grey, abdomen lighter ; iris very dark 
brownish-grey, feet light blue, webs flesh-colour, bill bluish-black all over. 
Nestling. Covered with black down. Also varying from dark brownish-grey to very light grey 
or almost white. 
Nest. The egg is laid in a depression on the branch of a tree or on a point of rock. 
Eggs. Clutch one ; ground-colour stone, blotched all over with reddish-brown and lavender. 
Some examples have a resemblance to the eggs of Chlamydera. Dimensions 44-42 mm. 
by 33. 
Breeding-season. October to February. 
Eggs. Many eggs were found on Norfolk Island on the 4th of February, 1913, 18th of November, 
1912, 3rd of January, 1912, 9th of January, 1913, 6th of February, 1913, and 30th of 
October, 1912. The well-known eggs have often been described and figured, and vary 
very much. Those from Norfolk Island measure : 44'5 X 3T3, 45'5 X 31'5, 42 X 32 to 
47'5 X 32'5,48'5 X 30‘8, 503 X 33’6mm. 
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