436 Letters, Announcements, ^c. 



perah, Eastern Bengal, contains one remarkable novelty, Hy- 

 drochelidon leucoptera, a beautiful specimen in full plumage. 

 There can be no doubt of the species ; for it corresponds with 

 Yarrell's figure and description (B. B. 3d ed. iii. pp. 532-536), 

 except that the dimensions are larger than those he gives. 

 Length 9'4 in., wing from carpal joint 8*3, bill from front 1, 

 from gape 1*35. It has the black under wing-coverts, the 

 pure white tail, and upper and under tail-coverts, and deep 

 black head, neck, throat, breast and abdomen. It is possible 

 that this species has already been noticed by some other ob- 

 server ; but I believe it to be new to our avifauna. 



Then he has brought me several specimens of an Arachnech- 

 thra, which he fancied was A. lotenia; but it is smaller, and has 

 the deep purple-black abdomen of A. curriicaria, which these 

 specimens in fact resemble in every particular, except that 

 they are slightly larger, and their bills conspicuously so. This 

 difference is constant, and, coupled with the somewhat larger 

 and more brilliant axillary tufts, seems to demand specific sepa- 

 ration. The difference in the bills of the two races is most 

 marked. Taking Mr. Gould's figures (B. As. pt. vii.) of A. 

 currucaria and A. lotenia, the bill of 



-V- A. INTERMEDIA, 



as I propose designating the Tipperah race, is exactly interme- 

 diate, and these figures correspond accurately with numerous 

 specimens in my collection. Actual measurements scarcely con- 

 vey an adequate idea of the marked difference in size; but I sub- 

 join the lengths, measured with compasses, from the forehead 

 to the tip of the upper mandible, in eleven specimens, from 

 various localities, of A. currucaria, and six of A. intei'media from 

 Tipperah : — 



A. currucaria. 



Mirzapoor, c? 



Gorgaon ,, 



Lahore ,, 



Simlah ,, 



A. intermedia. 



6 -8, 6 -73, c? -73, d -72; ? 73, ? '12. 



