THE BIRDS OF NORTHERN THAILAND 85 



over the upper back white; the remaining upperparts glossy black; 

 many white spots on the expanded wing and tail; a broad line 

 back from the eye black; the throat, thighs, and under tail coverts 

 ferruginous; the remaining underparts white, washed with ferrugi- 

 nous on the abdomen. The immature has the forehead a'nd supercilium 

 pale ferruginous and the throat pure white. 



NEOHIERAX INSIGNIS CINEREICEPS (Stuart Baker) 



Tenasserimese White-rumped Falcon 



Polihierax insignis cinereiceps Stuart Baker, Bull. Brit. Orn. Club, vol. 47, 1926, 

 pp. 101-102 (Myawadi, Tenasserim). 



Poliohierax insignis, Gyldenstolpe, Journ. Nat. Hist. Soe. Siam, 1915, p. 234 

 (listed) ; Kungl. Svenska Vet.-Akad. Handl., 1916, p. 131 (Khun Tan) ; Ibis, 

 1920, p. 749 ("Northern Siam"). 



Neohierax insignis cinereiceps, de Schauensee, Proc. Acad. Nat. Sci. Philadel- 

 phia, 1929, p. 577 (Doi Suthep) ; 1934, p. 269 (Mae Taeng, Chiang Mai).— 

 Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 1931, p. 165 (Doi Suthep) ; 

 1936, p. 78 (Doi Suthep).— Riley, U. S. Nat. Mus. Bull. 172, 1938, p. 58 

 (Doi AngKa). 



The pretty white-rumped falcon is apparently restricted to the 

 dry lowland deciduous forests (pa daeng) of Mae Hong Son, Chiang 

 Mai, and Lampang Provinces, where it is locally fairly common. 

 Eisenhofer sent to Stockholm five specimens from Khun Tan; I col- 

 lected it at Ban Sop Mae Chaem, Chom Thong, Doi Pha Lat, Ban 

 Mae Mo, and about 27 km. north of Chiang Mai. I have found 

 it in some numbers in the neighborhood of Ban Mae Klang (at the 

 foot of Doi Ang Ka) and along the highway north of Chom Thong. 

 At Chiang Mai it appears uncommonly in winter at the base of Doi 

 Suthep, where I have seen it between October 23 (1930) and Jan- 

 uary 28 (1933). 



This is one of the tamest of raptorial birds. I have often found 

 it perched on a low branch of a leafless tree or even upon a pile of 

 the material used to metal the roads and have thrown handfuls of 

 stones and gravel all around it without causing it to fly. From its 

 post of observation it makes swift dashes to the ground, where it 

 remains to eat its prey, which is usually grasshoppers. De Schau- 

 ensee took a bird whose stomach contained only charcoal ; it may be 

 noted that charcoal kilns are numerous in the type of forest in which 

 it dwells. The flight of this falcon is dipping, like that of a wood- 

 pecker, and quite unlike that of other Thai species. 



The feathers become very abraded from the coarse leaves of the 

 dry forest, and then the dark portions of the plumage become dis- 

 tinctly brownish. A specimen taken on December 2 has one fresh 

 black central rectrix in the otherwise brownish black tail. 



My specimens had the irides brown ; the orbital region, lores, and 

 cere yellow ; the maxilla black, with the basal half yellow ; the man- 



