64 H. H. Godwin- Austen — List of the Birds collected [No. 2, 



ance only. In the subsequent observations, by regulating the flow of air, 

 the temperature is to be lowered very gradually as it approaches the point 

 noted ; and on the first appearance of dullness, the blast is arrested, but 

 the reading of the thermometer is not to be taken till it reaches its lowest 

 point. 



There are other points to be attended to, which unpractised observers 

 frecpxently neglect. One is to keep the eye on the same level as the top of 

 the mercurial column of the thermometer (whether that of the hygrometer 

 or psychrometer) when taking the reading, in order to avoid the errors of 

 parallax. This is a point which it is most difficult to enforce on those who 

 are not thoroughly trained observers, and such persons are few in India. 



The capsule must not be more than three parts filled with ether, and 

 at first a very gentle blast must be applied or the ether will spill over the 

 surface of the capsule ; and if not perfectly pure, will impair its polish. 

 The ether must be free from water. 



VIII. — List of the Birds collected on the Expedition into the Bajta Sills, 

 Assam, together with those obtained in the adjacent JDarrang Terai. — 

 By Major H. H. Godwin-Austen, F. B. G. S., M Z. S., Sfc, Dep- 

 uty Supt. Topographical Survey of India. 



(Received May 26th ;— Read June 7th 1876). 

 (With Plates III & IV.) 

 Having been placed in charge of the survey-party attached to the 

 force which, under the command of Brigadier- General W. J. F. Stafford, 

 C. B., penetrated into the Dafla Hills during the winter of 1874 — 75, an op- 

 portunity was presented of forming collections in a portion of the N. E. 

 Frontier which had never before been visited. It was an opportunity not 

 to be lost, as it would extend considerably the undoubted range of many 

 interesting or little-known Himalayan forms towards the east into the 

 Indo-Burman and West China faunas ; while there was also the great proba- 

 bility of discovering new forms, not only among the birds, but in other 

 branches of zoology. On arriving in Calcutta in October 1874, I received 

 much assistance and advice from Messrs. Wood-Mason and G. Nevill, of the 

 Indian Museum, and at the recommendation of the former was permitted to 

 entertain and take with me a native taxidermist, with extra coolies for the 

 carriage of specimens, store-boxes, &c. ; my cordial thanks are due for this 

 aid and for the interest shewn by the above-named gentlemen. The list 

 shews that I was tolerably successful, notwithstanding that the force did 

 not penetrate beyond the first large valley at the back of the outer range, 



