480 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



Phylloscopus reguloides reguloides [partim], Riley, U. S. Nat. Mus. Bull. 172, 



1938, p. 435 (Khun Tan [partim]). 

 Phylloscopus reguloides claudiae, Riley, U. S. Nat. Mus. Bull. 172, 1938, p. 435 



(Khun Tan). 



Dr. Ticehurst has identified as claudiae two males taken by Smith 

 on Doi Khun Tan, 3,000 and 4,000 feet, February 22, 1932 ; a male 

 from Ban Samoeng, November 23, 1935; and a female from Ban 

 Muang Sum, December 25, 1936. Two specimens considered by him 

 intermediate between claudiae and assamensis have already been listed 

 under the latter name. 



P. r. claudiae "resembles assamensis, but the upper parts slightly 

 brighter, not so yellowish-green; cheeks and mesial coronal streaks 

 greyer yellow and paler; under parts whiter, any yellow being con- 

 fined to streaks on the breast, no wash of yellow ; two outer pairs of tail 

 feathers only very narrowly and sharply edged with white . . . Inter- 

 grades with assamensis, and not every specimen can be placed" (Tice- 

 hurst, Systematic review of the genus Phylloscopus, 1938, p. 171). 



PHYLLOSCOPUS DAVISONI DAVISONI (Oates) 



Tenasserimese Lesser White-tailed Willow Warbler 



Acanthopneuste davisoni Oates, Fauna of British India, Birds, vol. 1, 1889, pp. 



420-421 (Mount Muleyit, Tenasserim ) . 

 Acanthopneuste trochiloides davisoni de Schauensee, Proe. Acad. Nat. Sci. 



Philadelphia, 1929, p. 555 (Doi Suthep). 

 Acanthopneuste reguloides davisoni, Deignan, Jour. Siam Soc. Nat. Hist. 



Suppl., 1931, p. 149 (Doi Suthep). 

 P[hyIloscopus] reguloides subsp., Chasen and Boden Kloss, Journ. Siam Soc. 



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

 Phylloscopus trochiloides davisoni, de Schauensee, Proc. Acad. Nat. Sci. Phila- 

 delphia, 1934, p. 231 (Doi Suthep, Doi Chiang Dao). 

 Acanthopneuste reguloides harterti, Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 



1936, p. 117 (Doi Suthep). 

 Acanthopneuste davisoni, Deignan, Journ. Siam Soc. Nat. Hist. Suppl., 1936, p. 



117 (Doi Suthep). 

 Phylloscopus flavo-olivaceus flavo-olivaceus, Riley, U. S. Nat. Mus. Bull. 172, 



1938, p. 436 (Doi Suthep, Doi Langka, Doi Hua Mot). 

 Phylloscopus davisoni davisoni, Gkeenway, Bull. Mus. Comp. Zool., 1940, p. 



1S9 (Doi Ang Ka). 



This bird is a common permanent resident in the more open ever- 

 green at altitudes in excess of 4,500 feet, occurring on all the north- 

 ern mountains of sufficiently high elevation (Doi Ang Ka, Doi Su- 

 thep, Doi Chiang Dao, Doi Pha Horn Pok, Doi Langka, Doi Hua Mot, 

 and Phu Kha). It is the only species of Phylloscopus likely to be 

 found in summer in Thailand. 



A male from Phu Kha, April 15, had the gonads enlarged. Post- 

 nuptial molt is shown by a long series of examples taken between 

 June 22 and November 3. The period of prenuptial molt is still un- 



