Vol. III. 

 1 903 



MlLLIGAN, Description of a New Gymnorhina. QJ 



one of the Museum collectors on the Cane and Ashburton Rivers, 

 North-Western Australia, and which bore, at first sight, a 

 striking resemblance to Gymnorhina tibiccn (Latham) of 

 Eastern Australia, except for their conspicuously long and 

 narrow bills. 



A closer examination and comparisons with a pair of mounted 

 specimens of Gymnorhina tibiccn in the Museum and with re- 

 corded scientific descriptions of that species disclosed so many 

 points of difference as to warrant the separation of the Western 

 form, and I therefore declare it a new species. My grounds for 

 separation are briefly as follow : — (a) The Western bird is longer ; 

 (b) its bill is longer, more narrow, less arched, and more triangular- 

 shaped ; (c) its tail is shorter ; (d) its tarsi are shorter ; and (<?) the 

 thigh feathers are not black, but wholly white for the upper 

 portion, and noticeably so for the lower. In addition, the 

 plumage generally does not present the striking and decided 

 contrasts of glossy bluish-black and snowy-white that mark the 

 Eastern forms. 



In support of the first ground of separation, I find that the 

 measurements of the skins of the two oldest birds of the new 

 species (one from the Cane River and the other from the Ash- 

 burton River) are respectively 15.5 and 16.6 inches, while those 

 given by various authorities vary from 15 to 15.75 inches. As 

 regards the second ground, the measurements of the culmen of 

 the same two skins are 2.4 and 2.5 inches and in the three others 

 (all young birds) the measurements of the same organ are 2.25, 

 2.25, and 2.1 inches, while the recorded measurements of Gym- 

 norhina tibiccn are given by one trustworthy authority as 2.1 

 and 2.2 inches, and by another as 2 inches in the male and 1.7 

 inches in the female. The culmen of each of the mounted 

 specimens in the Museum measures 1 .9 inches. The girth of 

 the mandibles taken at the forehead is 2.25 inches in the new 

 species, and 2.5 in the mounted specimens referred to. In 

 the former, too, the arch of the upper mandible is almost 

 inappreciable, and the contour lines of the upper and lower 

 mandibles form together an acute-angled triangle, or nearly 

 so. On the third ground, the tails of the five skins of the 

 Western form measure 5.1, 5.4, 5.5, 5.6,. and 5.6 inches, while 

 the authorities mentioned give those of Gymnorhina tibiccn 

 as 6, 6, 6.5, and 6.8 inches. On the fourth ground, the 

 measurements of the tarsi belonging to the same five skins are 

 2, 2.1, 2, 2, and 2.1 inches, while the measurements recorded in 

 the British Museum " Catalogue " are given as 2.3 and 2.4 inches. 

 Respecting the fifth ground, the feathers of the upper half of 

 the thighs of the one adult male are pure white, and of the lower 

 half some are white, others white with brownish margins, and 

 others brown with white margins. In a slightly younger bird 

 the upper half is white, as also the whole of the opposed inner 

 sides, while the outer sides of the lower half are blackish-brown 

 with white t'ps. In all the three young birds the thighs are 



