66 Mr. N. A. Severtzow on the 



48. ACROCEPHALUS ILENSIS, Sp. nov.* 



This is an intermediate form between the East-European 

 A. dumetorum, Blyth, and the western A. streperus, Vieill. 

 It is found in summer on the Hi and in Ferghana. In 

 August it appears in small numbers in the Pamir. 



49. Hypdlais caligata, Licht. 



Breeds in the Bash-Alai and near the sources of the Kash- 

 gar Darya, where it was found in July ; in August it migrates 

 through Central Pamir. 



50. Phylloscopus PSEUDO-BOREALisf^ Sev. 



Collected on the Pamir during its migration in August ; 

 also found breeding in the mountains of northern Ferghana 

 north-east of Namanghan, and since received from various 

 parts of the Tian-shan system, eastward as far as the Upper 

 Hi. While collecting I mistook this bird for P. borealis, 

 Bias., to which it is very closely allied, differing particularly 

 in having a much longer first primary, which is about '6". 

 The second primary equals the seventh, rarely a little longer 

 or shorter. In the primary quills, and them alone, it agrees 

 with P. viridanus, Blyth, and P. plumbeitarsus, Swinhoe ; but 

 all its other characters, such as size, proportions, bill, and 

 colouring, are those of P. borealis. 



Having now compared considerable series (though not all 

 my specimens), I find that, at any rate, the diflferences be- 

 tween my P. pseudo- borealis and both P. viridanus and P. 

 plumbeitarsus are much greater than those between the two last 

 named. Some of my specimens of P. plumbeitarsus were 

 determined by Mr. Seebohm during his last visit to Moscow ; 

 and my specimens of P. viridanus have been compared with 

 one of Mr. Brookes typical Indian specimens, which I received 

 from Mr. Dresser. 



* [Mr Seebohm lias examiBed examples of this supposed new species, 

 and considers tliem to be A. dumetorum in autumn plumage. Tliey agree 

 witli that species in wing-formula, and are imdistinguisbable from Indian 

 * examples shot in September. — Edd.] 



t [Two examples in Mr. Seebobm's collection are identified by him as 

 P. ]}hmibeitarsus, somewhat above the average size, but not larger than 

 examples from Pegu. — Edd.] 



