THE RACES OF THE NICOBAR MEGAPODE, MEGA- 

 PODIUS NICOBARIENSIS BLYTH. 



Br Harry C. Oberholser, 

 0/ the Biological Survey, United States Department of Agi'iculture. 



The Nicobar megapode, Megopodius nicohariensis, is of interest as 

 marking the extreme western limit of the geographic range of the 

 Megapodiidae. Furthermore, no members of this family live nearer 

 than the islands off the northern coast of Borneo and the islands in 

 the Java Sea. This species is, therefore, a geographic outlier, as it 

 were, and, as would be expected, apparently a very distinct species, 

 though not, however, distantly related to Megapodius teninherensis 

 Sclater and Megapodius cumingli Dillwyn. 



The material used in the present stud}^ is all in the United States 

 National Museum, and consists almost wholly of specimens collected 

 by Dr. W. L. Abbott. Measurements have all been made in milli- 

 meters, and in the manner described in the present author's paper on 

 Butorides virescens.^ The names of colors used are from Mr. Ridg- 

 way's recently published " Color Standards and Color Nomen- 

 clature." 



The geographic distribution of Megapodivs nicohariensis is limited 

 to the Nicobar Islands, off the western coast of the Malay Peninsula, 

 in the southeastern part of the Bay of Bengal, but the species is 

 found on practically all the islands of this group. It has been 

 supposed not to vary subspecifically on any of the islands; but by 

 our present examination two well-defined races are shown to exist, 

 which are hereinafter duly described. 



There is apparently no sexual difference, either of size or color, in 

 this species. Considerable individual variation is evident, however, 

 the olivaceous color in some specimens being much more rufescent 

 than in others. Also, what amounts to a gray color phase, inde- 

 pendent of sex or age, not infrequently occurs, in which the lower 

 parts are extensively slaty or dark grayish, and even the upper sur- 

 face is to some extent suffused with the same color. The racial 

 differences are shown in the following account of the subspecies. 



1 Proc. U. S. Nat. Mus., vol. 42, 1912, p. 533. 



Proceedings U. S. National Museum. Vol. 55— No. 2278. 



399 



