508 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



A single imsexed and undated example of the yellow wagtail, 

 collected by Eisenhof er at Khun Tan and now deposited in Stockholm 

 (under the name simillima), is without doubt the bird listed by Gyl- 

 denstolpe in 1915 as borealis; it is probably a representative of anga- 

 rensis. The race is otherwise known from our provinces by an adult 

 female taken at Ban Tong Yang, May 4, 1936, and a first-winter 

 female from Thattaf ang, October 16, 1936. Its status with us is still 

 uncertain but collecting may prove it to be as common a winter visitor 

 as M. f. macronyx, with which it associates. 



Adults of the present form may be separated from those of ma- 

 cronyx by their having a narrow white superciliary streak from the 

 base of the bill to the posterior ear coverts. The young in first-winter 

 dress differs from that of macronyx in having the under wing coverts 

 and axillaries olivaceous-yellow or creamy yellow and the posterior 

 flanks more or less strongly washed with yellow or cream. 



The specimens mentioned above and many others from Bangkok do 

 not agree with any of the yellow wagtails previously recorded from 

 Thailand. From plexa they differ in having the pileum sharply 

 demarcated from the mantle; from macronyx, in having a distinct 

 supercilium; from simillima, in having the supercilium less clearly 

 defined and narrower (particularly behind the eye). In the circum- 

 stances, I have no choice but to place them with Sushkin's race, which 

 has not otherwise been taken in winter quarters. 



It is highly unlikely that a form that breeds in Kamchatka and 

 winters chiefly in the more eastern Malaysian islands should ever 

 appear in the central and western portions of Indo-China, and records 

 for the occurrence of simillima in Burma and Thailand should be 

 viewed with skepticism. 



MOTACILLA CITREOLA CITREOLA Pallas 



Amur Yellow-headed Wagtail 



Motacilla citreola Pallas, Reise durch verschiedene Provinzen des russischen 



Reichs, vol. 3, 1776, p. 696 ("In Sibiria orientaliore"). 

 Motacilla citreola calcarata, Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 1931, 



p. 154 (Chiang Mai). 

 Motacilla citreola citreola, de Sohauensee, Proc. Acad. Nat. Sci. Philadelphia, 



1934, p. 238 (Chiang Mai). — Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 



1936, p. 121 (Chiang Mai). 



The yellow-headed wagtail is very locally common at Chiang Mai 

 from November 3 (1936) to February 10 (1936), after which date the 

 countryside becomes too dry for its taste ; it is otherwise recorded only 

 from Chiang Rai, where, along the Mae Kok, I found it in some 

 numbers as late as May 7, 1936. 



This species is even more partial to wet, grassy areas than Motacilla 

 flava and is never likely to be observed away from them. Its choice of 



