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(Five Doors from Charing Cross), 
Keep in stock every description of 
APPARATUS, CABINETS, BOOKS, AND SPECIMENS 
for Collectors of 
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Catalogue (96 pages) sent post free on application. 
Issued Monthly, Illustrated with Plates and Text Figures . 
To Subscribers, 15/- per annum, post free . 
The Scottish Naturalist 
With which is incorporated “ The Annals of Scottish Natural History.” 
A Monthly Magazine devoted to Zoology. 
Edited by James Ritchie, M.A., D.Sc., F.R.S.E., Keeper Natural History 
Dept. Royal Scottish Museum ; William Evans, F.R.S.E., Member of the 
British Ornithologists ’ Union ; and Percy H. Grimshaw, F.R.S.E., F.E.S., 
Assistant-Keeper , Natural History Dept., Royal Scottish Museum. Assisted by 
Evelyn V. Baxter, H.M.B.O.U. ; Leonora J. Rintoul, H.M.B.O.U. ; Hugh S. 
Gladstone, M.A., F.R.S.E., F.Z.S. ; W. Eagle Clarke, I.S.O., LL.D. 
EDINBURGH— OLIVER & BOYD, TWEEDALE COURT. 
LONDON— GURNEY & JACKSON 33, PATERNOSTER ROW. 
SCIENCE PROGRESS 
A Quarterly Review of Scientific Thought, 
Work and Affairs. 
Editor - COLONEL SIR RONALD ROSS, K.G.B., F.R.S. 
This Quarterly is now in its fourteenth year of publication. Its 
object is to give all readers of wide culture and interest in science 
a knowledge of the numerous advances which are being continually 
made in connection with scientific work and thought. Each number 
contains Recent Advances in Science (by a number of experts). 
Articles, Popular Science, Essay-Reviews, Correspondence, Notes, 
Essays, many Reviews, and a Book List. Published early every 
quarter by John Murray, 50a Albemarle Street, London, W. Annual 
Subscription 25/6 and price of one number 6s. Subscriptions 
through bookseller or direct to the Publisher. 
“ Science Progress, which has now reached its thirty-ninth 
number, not only covers a remarkable wide field with great 
ability, but has had impressed upon it, by the energetic and 
humane spirit of its editor, a certain dynamic quality which 
makes it a force as well as a source of light.” — The Times, 
Printed at Browns’ Savile Press, 40 George Street, Hull, and published by 
A. Brown & Sons, Limited, at 5 Farringdon Avenue, in the City of London. 
Aug. -Sept., 1922. 
