NO. 2121. RACES OF THALAS8EVS BERGI1—0BERH0L8ER. 



523 



Tlialasseus bergii cristatus with the pale coloration of Thalasseus hergii 

 pelecanoides. The present race seems to be confined to the southern 

 Philippine Islands. 



Measurements of specimens of Thalasseus bergii halodramus. 



THALASSEUS BERGII PELECANOIDES (King). 



Sterna pelecanoides King, Surv. Intertrop. and Western Coasts Aust., vol. 2, 1827, 

 p. 422 (Australia: i. e., Torres Strait, northern Queensland). 



Sterna bergeri [sic] ("Lecht." [lege "Licht."]) Ramsay, Proc. Linn. Soc. New 

 South Wales, 1878, p. 301 (based on "Gould, Bds. Aust. Handbook, II, 

 p. 394, sp. 601") (Torres Strait, northern Queensland). 



Suhspecijic characters. — Similar to Thalasseus hergii halodramus, 

 but decidedly larger. 



Measurements. — Wmg, 323-355 (average, 337.5) mm.; tail, 130-161 

 (147.7); exposed culmen, 55.5-66.5 (61); tarsus, 24.5-30 (27.6)." 

 Wing, 325-361 (343. 1).^ 



Geographical distribution . — ^The East India islands, Melanesia, and 

 northeastern Australia. Resident north to the Marshall Islands, 

 Admiralty Islands, New Guinea, Gilolo Island, Celebes, Borneo, and 

 the Natuna Islands; west to the southern Malay Peninsula and 

 Sumatra; south to Java, Savu Island, the Aru Islands, Queensland, 

 and the island of New Caledonia; and east to the New Hebrides and 

 the Solomon Islands. 



1 Used in measurement averages on p. 522. 

 ' Type. 



» Wing tips slightly worn. 

 * Eight specimens, from the East India islands. 



s Twenty-nine specimens, from the East India islands, the Admiralty Islands, and the Louisiade 

 Archipelago, measured by Stresemann. 



