349 
of Edinburgh, Session 1879-80. 
than two scientific papers previous to 1866. These two appeared in 
the Madras Journal , one in 1844-45 entitled “Descriptions of 
some supposed new or imperfectly described species of Birds,” the 
other in 1847 entitled “ Notice of the Habits of the Large Indian 
Boa or Bock Snake.” 
In 1862 Lord Arthur Hay assumed the title of Lord Walden on 
the death of his elder brother Lord Gifford, and for the next four 
years of his life was almost entirely occupied with his military and 
other duties, as indeed he had been for many years previously. He 
was present with his regiment at the various battles fought during 
the Crimean war, and passed through the whole of that memorable 
campaign with distinction. He took part in the siege of Sebastopol, 
and received, among other honours, the medal and clasp for the war, 
the Sardinian medal of valour, the Turkish war medal, and the 
fifth class of the order of the Medjidie. He was ultimately pro- 
moted in 1860 to a Colonelcy in the Grenadier Guards, but was 
placed on half pay in 1863. In 1866, after becoming a Lieutenant- 
Colonel of the 17th Lancers, he finally retired from the army, and 
betook himself to scientific pursuits. For the next ten years he 
resided at Chislehurst, during which period he contributed a most 
important series of ornithological papers to the “ Proceedings and 
Transactions of the Zoological Society,” the “Annals of Natural 
History,” “Rowley’s Ornithological Miscellany,” “The Ibis,” and 
other periodical magazines — many of these papers specially referring 
to the birds of India and the Eastern Archipelago. 
Upon the death of Sir George Clerk in 1868, Lord Walden was 
elected President of the Zoological Society of London — an office in 
which he discharged his duties in the most efficient manner until 
his death. 
Lord Walden succeeded to the peerage and estates on the death 
of his father in 1876 ; and at that time, having taken up his resi- 
dence at the family seat, Yester, in Haddingtonshire, he entered 
upon the investigation of the avi-fauna of the Philippine Islands, at 
which subject he worked with extraordinary zeal, the result being a 
most valuable series of papers, thirteen in number, which appeared 
in the “ Proceedings of the Zoological Society,” the last of which 
was finished but a day or two before the author’s death. 
The papers of greatest value written by Lord Tweeddale appeared 
