CAMBRIDGE FARM INSTITUTE SERIES 
GENERAL Epitors: T. B. Woop, M.A., and 
E. J. Russetz, D.Sc. 
The volumes of this series are intended to meet the needs of the 
many Farm Institutes already in existence or about to be formed. 
They are intended for the average student whose object is to farm, 
tather than for the exceptional man who wishes to become an agri- 
cultural expert. 
Now ready 
Farm Accounts. By C. S. Orwin, Hon. M.A. 3s net. 
A Student’s Book on Soils and Manures. By E. J. 
RUSSELL, D.Sc. 38 6d net. 
Fungoid and Insect Pests of the Farm. By F. R. 
PETHERBRIDGE, M.A. With 54 illustrations. 48 net. 
CAMBRIDGE AGRICULTURAL MONOGRAPHS 
General Editors: T. B. Woop, M.A., and 
E. J. RussEtt, D.Sc. 
Inorganic Plant Poisons and Stimulants. By WINIFRED 
E. BRENCHLEY, D.Sc., F.L.S., Fellow of University College, London, 
With 19 illustrations. Royal 8vo. 5s net. 
UNIVERSITY OF CAMBRIDGE SCHOOL OF 
FORESTRY BULLETINS 
The Production and Utilisation of Pine Timber in Great 
Britain. Part I. Production. By E. R. Burpon, M.A., Investi- 
gator in Timber, and A. P. Lone, B.A., Assistant Investigator. 
No. 1. Sample Plots of Scots Pine at Woburn. Demy 8vo. 
Paper covers. 1s 6d net. (Bulletin, No. 1.) 
No. 2. Sample Plot of Scots Pine at King’s Lynn. Demy 8vo 
Paper covers. gd net. (Bulletin, No. 2.) 
THE CAMBRIDGE NATURE STUDY SERIES 
General Editor: HuGu RicHarDson, M.A. 
Lessons on Soil. By E. J. Russevy, D.Sc. With 58 illustrations. 
Large crown 8vo. 1s 6d net. : 
The Gateways of Knowledge. An Introduction to the Study of 
the Senses. By J. A. DeLi, M.Sc. (Vict.). With 51 figures. Large 
crown 8vo. 2s 6d net. 
The Story of Our Trees in Twenty-four Lessons. By MarGaRET 
M. GREGSON, B.A. With frontispiece and 74 figures. Large crown 8vo. 
2s 6d net. 
Weeds. Simple Lessons for Children. By Rospert LLoyp PRAEGER. 
With 45 figures and 3 plates. Large crown 8vo. 1s 6d net. 
Bird Studies in Twenty-four Lessons. By W. PERcIvaL WESTELL, 
F.L.S., M.B.O.U. With frontispiece, 49 illustrations and a map. 
Large crown 8vo 2s 6d net. : auee 
Pond Problems. By E. E. Unwin, M.Sc. With frontispiece and 
48 illustrations. Large crown 8vo. 2s net. 
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