359 



nest, five or six being the usual number. In the autumn the migration lasts till the 10th of 

 October. In the Darasun district this bird is also common." A clutch of unidentified eggs sent 

 by Dr. Dybowski, Mr. Taczanowski surmises are those of this species. He compares them to 

 those of the Robin ; they are marked, he says, with reddish spots on a dull white ground, the 

 spots being more profuse at the larger end ; and, judging from Mr. Hume's notes as above given, 

 Mr. Taczanowski is, in all probability, correct in his surmise. 



Referring to the habits of this bird, Mr. Sabanaeff writes (7. c.) as follows : — " In habits the 

 Bluetail resembles the Flycatchers. It is constantly in motion in quest of insects, and resorts to 

 the tops of the trees, especially when they are lofty. It is consequently very difficult to shoot, 

 more so, if possible, than Phylloscopus borealis. Its song, which is not very often heard, is 

 peculiar, and resembles the syllables till, tul, tul, till, tul, tul, dee. It evidently breeds late ; for 

 on the 26th June, 1872, I found at Sosva a nest containing a single egg, which in appearance 

 resembled the eggs of the common Flycatcher (Muscicapa grisola), and on the 6th August, 

 1868, I met with some just-fledged young birds at the foot of the Pavdinsk .rocks, whereas near 

 the Pavdinsk works the young birds could fly about the middle of June." 



By some authors the present species has been divided into two forms — Nemura cyanura and 

 Nemura rufilata, Hodgs. ; but a perusal of Hodgson's description will at once show that his 

 Nemura rufilata is the very old male, whereas his Nemura cyanura is a younger bird in the 

 plumage resembling that of the female. Blyth treats of Nemura rufilata as specifically distinct, 

 stating that it lacks the white eye-streak and has this streak brownish ; but, judging from 

 specimens I have examined, I cannot believe that he is justified in making two species. I find 

 the eye-streak very variable in colour, it being much duller and browner in young birds ; and in 

 one very old male, which I have figured and described, the eye-streak is rich ultramarine blue, 

 with only a faint trace of white visible when the feathers are moved. 



The specimens figured are a very old male from Sikkim, and an adult female from Lake 

 Baikal. 



In the preparation of the above article I have examined the following specimens: — 



E Mus. II. E. Dresser. 



a, 6 ad. Sikkim, December 1874 (Mandelli). b, ? ad. Lake Baikal [Dybowski). c, ? . Cashmere, May 20th, 

 1876 {Captain J. Biddulph). d, 6 , e,f, 2 . Tingchow, China, December 1867 (R. Swinhoe). 



