AMERICAN JOURNAL OF BOTANY.— Devoted to all Branches 



of Botanical Science. 



Established 1914. Monthly, except August and September. Official Publication of the Botanical 

 Society of America. Subscription, $7 a year. Volumes 1-21 complete asavailable, $i7o. Single numbers, 

 $1.00 each, post free. Prices of odd volumes on re ]uest. Foreign postage : 40 cents. 



ECOLOGY. — Devoted to all Forms of Life in Relation to Environment. 



Established 1920. Quarterly. Official Publication of the Ecological Society of America. Sub- 

 scription. $4 a year. Back volumes, as available, $5 each. Single numbers, $1.25, post free. Foreign 

 postage: accents. 



GENETICS. — A Periodical Record of Investigations Bearing on 

 Heredity and Variation. 



Established 1916. Bi-monthly. Subscription, 86 a year. Single numbers, $1.25 post free. Back 

 volumes, as available, $7.00 each. Foreign postage : 50 cents. 



Orders should be placed wilh THE SECRETARY, BROOKLYN BOTANIC GARDEN, 

 1000 WASHINGTON AVENUE, BROOKLYN, N.Y., U.S.A. 



THE POLYTECHNIC, regent street, w.i 



DEPARTMENT OF CHEMISTRY 



Head of Department: H. LAMBOURNE, M.A., M.Sc, F.I.C. 



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Full prospectxts on application io the Director of Education 



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