THE BIRDS OF NORTHERN THAILAND 403 



A female of October 18 retains traces of the juvenal dress in having 

 the feathers of the forecrown suffused with deep brown, the center 

 of the lower breast and the wing band suffused with buff. A male 

 of October 19 is in postnuptial molt. 



The adult differs from that of schistaceus chiefly in having the crown, 

 nape, and back black, instead of slaty blue-gray, and the primaries 

 without a visible speculum. 



It is interesting to note that an example of scMstaceus was collected, 

 October 22, 1936, at the same locality as the series of immaculatus. 



MYOPHONUS CAERULEUS CAERULEUS (Scopoli) 



Chinese Spangled Whistling Thrush 



Oracula (caerulea) Scopoli, Deliciae florae et faunae insubricae, pt. 2, 17S6, 

 p. 88, sp. 42 (China, ex Sonnerat; type locality restricted to Canton, by 

 Stresemann, Abh. Ber. Mus. Tierk. Volkerk. Dresden, vol. 16, No. 2, 1923-1924 

 [=1924], p. 28). 



Myiophoneus caeruleus, Gtldenstolpe, Kungl. Svenska Vet.-Akad. Handl., 1916, 

 p. 61 (Khun Tan) ; Ibis, 1920, p. 479 (Khun Tan). 



Myiophoneus coeruleus coeruleus, Chasen and Boden Kloss, Journ. Siam Soc. 

 Nat. Hist. Suppl., 1932, p. 245 (Doi Suthep). 



Myoplionus caeruleus caeruleus, de Schauensee, Proc. Acad. Nat. Sci. Phila- 

 delphia, 1934, p. 212 (Doi Chiang Dao).— Riley, U. S. Nat. Mus. Bull. 172, 

 1938, p. 419 (Doi Ang Ka, Doi Langka). 



Myoplionus coeruleus coeruleus, Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 

 1936, p. 113 (Doi Suthep). 



Myiophoneus caeruleus caeruleus, Greenwat, Bull. Mus. Comp. Zool., 1940, p. 

 169 (Doi Ang Ka). 



The black-billed whistling thrush seems to be a fairly common 

 winter visitor to the higher mountains of the provinces west of (and 

 including) the Khun Tan chain, occurring from October 17 (Doi 

 Suthep) to March 15 (Doi Ang Ka) , at elevations between 4,000 and 

 7,000 feet. Gyldenstolpe's example, taken at Doi Khun Tan in May 

 1914, is of such exceptionally late date that it must represent a case 

 of delayed migration. 



My specimens of this race were collected, not along the mountain 

 streams where the resident M. c. eugenei is dominant, but in deep, 

 moist evergreen forest, where they fed on the ground among mossy 

 rocks and fallen trees and were not observed until, alarmed, they flew 

 up onto some low branch or rotting stump, before vanishing into the 

 fastnesses of the jungle. 



A male had the irides dark brown ; the bill black ; the interior of the 

 mouth bright yellow ; the feet and toes black ; the claws horny black. 



From M. c. temminckii, the present form differs only in its shorter 

 and less robust bill, which is wholly black in color. 



I cannot distinguish immansuetus (Ichang, Hupeh) from topo- 

 typical material of caeruleus. 



