STERNA. 91 



clouded with olive toward base; feet and tarsi blackish. Wing, 344; tail, 

 178; tarsus, 28; culmen, 62." (Bangs.) 



"Very common throughout the group, especially abundant about the 

 native fish-pens." (Bourns and Worcester MS.) 



This is much the largest tern found in the Philippines. Rather local 

 in its distribution but usually found not far from fish-corrals or where 

 schools of small fishes appear near the surface of the water. 



Philippine records of this species are usually recorded under Sterna 

 bergii, but the specimens probably belong to the variety 8. bergii boreotis. 

 The question can not be cleared up at present. 



81. STERNA AN/ESTHETA Scopoli. 

 PANAYAN TERN. 



Sterna ancestheta SCOPOLI, Del. Flor. et Faun. Insubr. (1786), 1, 92; 

 SAUNDERS, Cat. Birds Brit. Mus. (1896), 25, 101; SHABPE, Hand-List 

 (1899), 1, 136; GATES, Cat Birds' Eggs (1901), 1, 190; MCGREGOR 

 and WORCESTER, Hand-List (1906), 20. WORCESTER, Phil. Jour. Sci. 

 (1907), 2, sec. A, 275, pi. 1 (nesting place). 



Didicas Rocks (Worcester)', Panay (Sonnerat). African and Indian seas 

 to China, Japan, Moluccas, northern Australian, Pacific Islands; Gulf of Mexico, 

 Western Indies. 



"Adult in breeding plumage. Loral stripe black; upper forehead, 

 crown, and nape black; shoulders slate-gray, passing into dark grayish 

 brown on mantle ; no visible white on secondaries ; primaries umber-brown, 

 shafts black, the 'wedges' on inner webs very narrow and not sharply 

 defined; rump and principal tail-feathers grayish brown like the mantle, 

 but the streamers white on outer and upper portions of inner webs, and 

 the next pair of rectrices whitish at their bases; abdomen and breast 

 grayish white ; under wing-coverts and throat pure white. Bill, tarsi, and 

 toes black, the inner webs of the latter considerably excised. Length, 355 

 to 380; culmen, 45; wing, 262; tail, 190; depth of fork, 102; tarsus, 20; 

 middle toe with claw, 30. The sexes are alike in plumage. 



"Adult in winter plumage. Similar to the above, but the lores and 

 crown mottled with white for a short time. 



"Immature. Generally similar, but with more white on the head; 

 whitish tips to the feathers of the back, which, when fresh, are somewhat 

 gray; a dark line along upper wing-coverts, and less white on outer 

 rectrices. Full plumage is not attained until the bird is at least two 

 years old. 



"Young. Head streaked and mottled with brownish black ; feathers of 

 upper parts dark brown with rufous tips, which subsequently become 

 paler, approaching white, and finally wear away; under parts grayish 

 white. Bill and toes brownish." (Saunders.) 



