290 BULLETIN 17 2, UNITED STATES NATIONAL MUSEUM 



Dr. W. L. Abbott collected three males and four females in the 

 Mergui Archipelago (Chance Island, December 28, 31, 1899; Lough- 

 borough Island, January 25, 1900; Bentinck Island, March 8, 1900; 

 Hastings Island, December 11, 1900), 



The length of the outer tail feather and the size and twist of the 

 spatula vary enormously and apparently are of httle use in defining 

 the various races. The outer tail feather grows for some time, and it 

 is difficult to tell without a very close examination whether it has 

 reached maturity. The length of wing and the development of the 

 crest are the principal characters relied upon to distinguish the forms 

 occurring in Siam. 



This form has a moderate crest and is larger than the Malayan form 

 but is smaller than the form from the north, and the crest is less pro- 

 nounced. To the southwest the present form apparently goes as far 

 as the Isthmus of Kra or not quite so far. Eastward it apparently 

 extends into southern Indo-China. Dr. Smith took the northern form 

 on the Mekong below Vientiane, but whether it is the resident form in 

 this part of the country is not definitely known. Gairdner took D. p. 

 paradiseus in the Raheng district in western Siam though his birds 

 were intermediate. Specimens from southeastern Siam average a 

 trifle larger than birds from central and southwestern Siam. 



The series from the Mergui Archipelago collected by Dr. Abbott are 

 more or less intermediate between D. p. malayensis and D. p. ijaradi- 

 seus, but nearer the latter. They differ hardly sufficiently to be recog- 

 nized as an insular race. 



Ten males from central Siam measure: Wing, 150-165.5 (157.4); 

 outer tail feather, 318-395 (366.3); middle tail feathers, 134-142.5 

 (137) ; culmen 25-27.5 (25.9) mm. Ten males from eastern and south- 

 eastern Siam: Wing, 154-166.5 (159.4); outer tail feather, 320-400 

 (342); middle tail feathers, 134.5-146 (138.9); culmen, 27-29 (27.5) 

 mm. Three males from the Mergui Archipelago: Wing, 155-160 

 (157); outer tail feather, 343-425 (382.7); middle tail feathers, 129- 

 141.5 (133.5); culmen, 27-29 (27.7) mm. Four females from the 

 Mergui Archipelago: Wing, 152-154.5 (152.6); outer tail feather, 

 320-345 (330.5); middle tail feathers, 126-133.5 (129.4); culmen, 26- 

 27 (26.6) mm. 



A young male taken by Dr. Smuth at Ban Sadet, Sriracha, J\me 1, 

 is about halt grown. It resembles the adult but is duller below, though 

 a band across the chest has begun to develop metalHc tips to the 

 feathers; the spatulae to the outer tail feathers have not cleared the 

 sheath yet but already have the characteristic twist; the crest is short 

 and feathery; there are no white spots below. 



Several older immature females in the series taken in fall have the 

 breast feathers tipped with white. The question arises as to whether 

 there is a sexual difference in the immature or whether both sexes have 



