206 



PROCEEDINGS OF THE ACADEMY OF 



[April, 



This new race is quite different from true Collocalia linchi, the only 

 form of the species with which it agrees in size, and it may readily be 

 distinguished on even superficial comparison by the difference in the 

 color of the upper parts. The best and most uniform character is the 

 always much more bluish or purplish color of the upper surface of the 

 tail. A single adult male from Linga Island, southeast of Singapore, 

 is intermediate between cyanoptila and linchi; but there is so much 

 purplish and bluish in the color of the upper parts, and the tail is so 

 nearly like that of cyanoptila, that the specimen must apparently be 

 referred to the latter, although this island is far from the Natuna 

 group, and in a location where linchi is the form we should naturally 

 expect to find. Further examples from Linga may, however, show 

 that the average characters of the bird found there will place it with 

 linchi. 



Measurements of the adults of Collocalia linchi cyanoptila are as 

 follows : 



Collocalia linchi affinis Beavan. 



Collocalia affinis Beavan, Ibis, 1867, p. 318 (ex Tytler MS.). 



Chars, suhsp. — Similar to Collocalia linchi cyanoptila, l^ut very much 

 smaller. 



Type locality. — Port Blair, South Andaman Island, Andaman 

 Islands. 



GeograpJiical distribution. — Andaman and Nicobar Islands. 



This form, long ago described from the southern Andaman Islands 

 by Beavan, has hitherto usually been considered the same as linchi. 

 The satisfactory series obtained by Dr. W. L. Abbott in the Nicobar 

 Islands, however, now conclusively establishes its claim to recognition. 

 It differs from true linchi in its much smaller size, and the decidedly 

 bluish or purplish shade of the upper surface, particularly the tail- 

 coverts and tail. 



" Type. 



