168 BULLETIN 186, UNITED STATES NATIONAL MUSEUM 



The Tenasserimese race of the malkoha is apparently restricted in 

 our provinces to the districts west of, and including, the Khun Tan 

 range. At Chiang Mai it was common on the plain and in the more 

 open evergreen of Doi Suthep from 2,000 to 3,500 feet, rarely to 4,500 

 feet. On Doi Ang Ka I found it both in the partially cleared valley 

 under Fha Mon and in the evergreen to 5,000 feet. Eisenhofer sent 

 to Stockholm 24 undated skins from Khun Tan. 



This cuckoo seeks concealment in dense thickets and in liana- 

 bound trees at the edge of the forest, making its way with remarkable 

 agility through the interlaced stems. As it progresses lengthwise 

 along a branch, with a long tail extending straight behind (but tend- 

 ing to droop slightly near the end), it markedly resembles a squirrel, 

 and this similarity is honored in the vernacular name nok hamg hok. 

 The call is a low cuck-cuek-cuck-cuck. 



I have no definite information on the breeding of this form, but 

 the nesting season must be very protracted; an immature specimen 

 from Chiang Mai, July 9, appears to be virtually equaeval with 

 another from Chom Thong, November 3. 



The July immature is very worn generally and is just beginning 

 to acquire fresh rectrices ; the November bird has completed the body 

 molt but is still molting the quills of both tail and wings. The tail 

 of this cuckoo becomes excessively abraded and in worn examples the 

 white tips are often much reduced in size or entirely lost : an adult 

 from Doi Langka, November 18, has obviously only recently molted 

 but already shows signs of wear in the tail. 



A Chiang Mai male had the irides brown; the orbital skin bright 

 crimson ; the bill apple green, red at the base of the maxilla ; the rictus 

 red ; the feet and toes grayish olive ; the claws slate. A female from 

 the same locality had the irides crimson; the orbital skin lake red; 

 the bill apple green, red at the base of the maxilla and about the nares ; 

 the feet plumbeous ; the toes brownish plumbeous. 



The malkoha has the head and back deep gray, changing to a glossy 

 oil green on the wings and tail; the rectrices tipped white (very 

 obvious from below) ; the underparts gray, deepening in shade toward 

 the vent and more or less suffused with ochraceous on the throat 

 and breast. 



RHOPODYTES TRISTIS SALIENS Mayr 



Tonkinese Large Green-billed Malkoha 



Rhopodytes tristis saliens Ma ye, Ibis, 193S, pp. 306-307 (Chapa, Tongking). 

 Rhopodytes tristis hainanus [partim], Gyldenstolpe, Kungl. Svenska Vet.-Akad. 



Handl., 1913, p. 58 (Den Chai, Ban Huai Horn) ; 1916, p. 104 (Pha Kho) ; 



Journ. Nat. Hist. Soc. Siam, 1915, p. 233 (listed). 

 Rhopodytes tristis longicaudatus [partim], Gyldenstolpe, Ibis, 1920, p. 595 



("Throughout the whole country"). — Riley, U. S. Nat. Mus. Bull. 172, 1938, 



p. 135 (Ban Nam Khian). 



