24 ON BIRDS FROM TENASSERIM. [1S6G. 



.Tcrdon and Blyth. 1 refer Captain Bcavan's specimens to Mr. Blyth's species with some doubt- 

 Dr. Jerdon, in his recent work, reduces D. intermedins, Blyth, to a synonym oi D. longicatidatus, 

 A. Hay ; yet Mr. Blyth's description appears to agree better with some individuals of the ashy 

 group. Moreover he mentions that it is intermediate between D. ccerulescens (Linn.) and 

 D. loTif/icaiulatus, A. Hay, whence doubtless his designation ; and at the time, Mr. Blyth was 

 unacijuainted with the true Javan D. cinentceus (Horsf.). Mr. Blyth's t>iie came from Penang ; 

 and as I have never met with a specimen of Ashy Drongo, or of the other species, from so far 

 south in the Malayan peninsula, I am unable to identify' Mr. Blyth's bird ; but in his 

 ' Catalogue of the Calcutta Museum,' he has enumerated under this title another specimen from 

 Moulmein. I have, however, good reason to believe that a race of the lonfjicaudatus group 

 also inhabits Teuasserim ; and it is not impossible, it is even probable, that the Malayan race is 

 distinct from that of Burmali. Until Penang specimens are actually compared with the 

 Moulmein race, the correct title of the latter must remain undetermined. From the Javan 

 species, these specimens differ by being altogether of a darker bluish ashy ; the wings are of a 

 P.Z.S. 1S6G, greenish black, rather than a greenish ashy; the tail is more deeply forked, and not so decidedly 

 P"°^'' cinereous on the upper surface; the bill is more compressed. All these points evince an 

 approach to I). loiif/icaudatus, and excite a suspicion of hybridism. But they are probably 

 nothing but the characteristics of an intermediate species — a link of transition, many of 

 which are to be found in the unstable family of the Dicruridce. The type of Vieillot's genus 

 Bicrurushemg Corvus balicassius, Linn. {=zEdolius viridescens, Gould, =.Balicassius philippensis, 

 Bp., ex Manilla), a totally distinct generic form, the long Fork-tailed Drongos must be referred 

 to the next generic synonym, Buclianrja, Ilodgs., the type of which is Edolius olbirictus, Hodgs., 

 ex Xipaul. The following are the principal measurements of the Tenasserim race : — 



Wing oj inches ; bill from nostril f; bill from forehead 1; uropygials 3J ; outer rec- 

 trices 5|. 



Somewhat larger than the Javan bird, it is considerably smaller than the Himalayan 

 £. pyrrhops, Hodgs. The Himalayan race of B. longicaudata has yet to be described and named. 

 It is a well-marked form, and very distinct from the Malabar type. 



19. MixoRXis RrBiCAPiLL.\ (TickcU). 



Motacilla ruhicapilla, Tickcll, J. A. S. B. 1833, p. 576. no. 27. 



No. 40. Salween Valley. 



The type of this species was procured by Colonel Tickell in Burrublioom, a district of 

 Central India. AVhen compared with specimens from ^launbhoom, a neighbouring district of 

 Central India, this Tenasserim specimen exhibits no difference beyond that of the bill being percep- 

 tibly longer ; and when compared with Himalayan specimens no difference whatever can be 

 detected ; and Mr. Hodgson's specific titles oichloris and rujiceps given to the Himalayan race have 

 therefore been correctly superseded by Dr. Jerdon. In the ' Catalogue of the Calcutta Museum ' 

 Tenasserim is given as the habitat, not only of this species, but also of J/, gular/s (Horsf.). This 

 last species is very distinct, and was founded on the 2IutaciUa (jularis. Raffles, Tr. Linn. Soc. xiii., 

 his type being from Sumatra, and not fi'om Java — a fact which has been overlooked by almost 

 every writer, the mistake probably arising out of KafHes's bird having been figured and described 



