1871.] VISCOUNT WALDEN ON THE BIRDS OF CELEBES. 329 



appeared very late in autumn. I find the following entries in an old 

 note-book of mine : — ' The first larger white-rumped Swallows I 

 have seen this season appeared to-day (March 18, 1865); but a very 

 few were visible, though the day was sultry and still.' ' They con- 

 tinued to pass every day, observing a north-easterly direction, until 

 the 25th, when a storm came up from the south and cooled the air.' 



" But other years they have appeared in spring or early in summer, 

 and, from the south-westerly direction to which they proceed at such 

 times, I am inclined to believe that their summer habitat is in the 

 mountain-region of Western Patagonia. It is remarkable that some 

 years they have continued to pass all, or a greater part of, the hot 

 season, and sometimes appear in vast numbers. Thus in the autumn 

 of 1863 I had a good opportunity of observing them here, as every 

 day thousands of them would descend to the stream near my house 

 to glide over the surface, sip and dip themselves in the water in the 

 manner common to all the Swallows. All the birds that arrived 

 through the hotter part of the day would remain by the stream and 

 congregate by thousands on the bushes ; but two or three hours 

 before sunset they would rise up and scatter about the sky and then 

 proceed north or north-east ; this continued for many days ; and they 

 have never since been so numerous. 



"They do not, like other birds, when migrating proceed with 

 a rapid flight in a straight line, but are always seen leisurely circling 

 about the sky with a serene graceful flight, never in close flocks, but 

 scattered about here and there — first one bird passing, a minute or 

 so afterwards another, then two or three, and so on for a great 

 part of the day. 



"Their notes differ much from those of all our other Swallows — 

 the birds incessantly uttering, as they circle about on high, a series of 

 remarkable sounds resembling somewhat the creaking of the ungreased 

 axle of a vehicle dragged along at a very slow rate of speed. 



" In my next letter I will proceed to describe the other Swallows 

 found in this neighbourhood." 



Professor Flower, F.R.S., exhibited, and made remarks on, the 

 mounted skeleton of the young Hippopotamus {Hippopotamus am- 

 phibius) recently born in the Society's Gardens, which had been 

 prepared for the collection of the Royal College of Surgeons. 



The skin of this specimen, which had been likewise mounted, was 

 stated to have been placed in the Giraffe-house in the Society's Gar- 

 dens for the examination of visitors. 



The Viscount Walden, President of the Society, read a memoir on 

 the birds of the Island of Celebes. Lord Walden commenced his 

 paper with the following observations : — 



" Situated in the midst of the vast collection of islands which 

 contribute to form the Malay archipelago, Celebes possesses an avi- 

 fauna of a type peculiar to itself. The geographical position of the 

 island and the leading characteristics of its fauna have been so clearly 



