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ON DIFFERENCES BETWEEN GULDENSTADT'S REDSTART 

 AND ITS EASTERN ALLY. 



By the HON. WALTER ROTHSCHILD. 



HAVING recently received, through the agency of Mr. Schluter, three Mart's and 

 oue/etnale of Biiticilla eri/tlu-ogastra from the Cancasns, I was much struck 

 by their very dark and intense coloration. On comparing them with my large 

 series from Tsaidam and Gansu in China, Eastern Turkestan, the Issyk Kul, and 

 Gilgit, received from the Petersburg Museum, Tancre's collectors, and in the Elwes 

 collection, the following differences are obvious : 



The red of the rump, al>diimen, and np])er tail-coverts is much darker and more 

 chestnut than in the Asiatic birds. The tail is very much darker and washed with 

 blackish brown, while it is pale rusty red in the Eastern bird. Ih.^ female is darker 

 and more ashy grey all over, and the tail also is darker and less washed with 

 grey. 



In looking up the synonymy of these two birds, I find that in every book 

 where these birds are mentioned, except in Pleske's and Lorenz's writings, the two 

 forms are mixed up. Lorenz and Pleske, however, noticed the differences, but 

 unfortunately the former bestowed a fresh name on the Asiatic bird, which had two 

 already. I do not agree with Pleske in considering these two forms as " varieties," 

 for I cannot find any mention of nor have I myself seen any connecting links ; on 

 the contrary, I am convinced they are very distinct species with different habitats. 

 The names of the two species must stand as : — 



1. Ruticilla erijthrogastra (Gtild.) for the Caucasus bird. 



2. Huticilla granrlis Gould for the Asiatic bird. 



The synonymy is as follows : — 



1. Motacilla enjthrogastra, Gilldenstadt in Xov. Com. Pctrop. XIX. p. 409, pis. 16, 



17 (177o) (Caucasus) ; Cliestnut-hellied Warhler, Latham, Synopsis, II. 

 pt. 2, p. 424 (1783) (Caucasus) ; Sylvia enjthrogastra, Latham, Ind. Orn. II. 

 p. 513 (1790) (Caucasus) ; Motacilla ceraunia, Pallas, Zoogr. Rosso- As. I. 

 p. 478 (Caucasus) ; Ruticilla enjthrogastra of modern authors (j)artim — 

 when referring to birds from the (."aucasns ! Plate : Dresser, B. FAirope, 

 II. pi. 46). 



2. Ruticilla grandix, Gould in Proc. Zool. Sac. 1849, p. 112 (Afghanistan and 



Thibet); "A tricolor, Gould, Proc. Zool. Soc. 1849" {sic), Bonaparte, 

 Consp. Ar. I. p. 296 (As. centr.) (This is evidently a lapsus calami, no 

 such name being published) ; R. vigorsi, Moore in Proc. Zool. Soc. 1854, 

 p. 27, pi. LX. (N. India 1) ; R. erijthrogaster n. var. severzovi, Lorenz, 

 Beitr. z. Kenntn. d. orn. Fauna d. Nords. d. Kaukasus, p. 23 (1887) 

 (Central Asia) ; R. enjthrogastra var. ssewerzowi, Pleske, Wisseiuch. 

 Result. Przewalski's Reis. II. Viigel, Lief. 1, p. 58 (1889) (Central Asia) ; 



