466 bulletin: museum of comparative zoology. 



feet from the ground and close to the trunk, July 12, containing 

 two downy young and a broken egg. The old female and the two 

 young were secured. Another nest in an exactly similar position, also 

 in a larch, was discovered July 10; both old birds, two downy young 

 and one egg were taken. 



The downy young can be separated from those of the kestrel by 

 their being clothed in dull grayish down, whereas young kestrels of 

 the same age wear a coat of whitish. 



Cotypes, from Tchegan-Burgazi Pass, Altai Mountains, Siberia. 

 A mated pair of adults, Nos. 57,672 <? and 57,673 9 , M. C. Z. 

 Collected July 10, 1912, by N. Hollister. 



Characters. The chief character of this new form is its very long 

 wings and tail — each of which are about an inch longer, than in 

 corresponding sexes, of any of the other races of the merlin. Colors 

 above about as in F. aesalon pallidus (Suschkin) or even paler, compari- 

 son with F. aesalon aesalon Tunstall of Europe is therefore unneces- 

 sary. On the under surface the darker markings are very small and 

 much blended with the ground color, producing a very pallid effect. 



Comparing these measurements with those of merlins from else- 

 where it is at once seen that the wings and tail of the Altai bird are 

 very long; the foot decidedly small; the tarsus and bill no longer. 

 The proportions of the bird are therefore quite different. 



Remarks. Two forms of the merlin recently described are — 

 Lithofalco aesalon pallidus Suschkin, 1 which in the breeding season 

 occupies the Kirghiz Steppes, the valleys of the Ural River and 

 tributaries, and the Mugodjar range, and winters in Turkestan and 

 N. W. India, and Aesalon regulus insignis Clark 2 of Korea. 



Comparing the type of insignis with a specimen of pallidus from 

 eastern Turkestan in exactly similar plumage, I find myself unable 

 to distinguish them. Again an adult male taken in winter at Tokio, 

 Japan, agrees almost exactly with an adult male of pallidus taken 



i Bull. B. O. C, 1901, 11, p. 5. 



2 Proc. U. S. nat, mus., June 15, 1907, 32, p. 470. 



