﻿Malt^er prises in IKlatuval Ibistoi v 



BY the provisions of the will the late Dr. "William Johnson Walker two prizes are annually offered by the Boston 

 Society of Natural History for the best memoirs written in the English language on subjects proposcU by a 

 Committee appointed by the Council. 



For the best memoir presented, a prize of $60 may be awarded ; if, however, the memoir be one of marked merit, 

 the amount may be increased to $100, at the discretion of the Committee. 



For the next best memoir, a prize not exceeding $50 may be awarded. 



Prizes will not be awarded unless the memoirs presented arc of adequate merit. 



The competition for these prizes is not restricted, but is open to all. 



Attention is especially called to the following points: 



t. In all cases the memoirs are to be based on a considerable body of original and unpublished work, accompanied 

 by a general review of the literature of the subject. 



a. Anything in the memoir which shall furnish proof of the identity of the author shall be considered as debarring 

 the essay from competition, 



3. Preference will be given to memoirs showing Intrinsic evidence of being based upon researches made directly 

 in competition for the prize. 



4. Each memoir must be accompanied by a sealed envelope enclosing the author's name and superscribed with a 

 motto corresponding to one borne by the manuscript^ and must be in the hands of the Secretary on or before April i of the 

 year for which the prize is offered. 



FOR. 1Q03 



1, A monograph of any genus or group of Thallophytes. 



2, Contributions to the life history of Sporozoa, 



SUBJECTS FOR. 1904 



T. The reactions of organisms to solutions, considered from the standpoint of the chemical theory of dissociation. 



2. Relations of plants to electricity. 



3. A statistical study of the relative cross-fertility between the varieties of a species, 



4. The chemical and physical reactions in cell narcosis. 



5. Causes of volcanic eruptions, 



6. The effects of past or present physical changes of the earth's surface on the development of species (^. ^,, river 

 work, changes of sea level, mountain building, etc.). 



Boston Society of Natural History 



Boston, Mass., L\ S, A, 



QLOVER M. ALLEN, Secretary 



INTERESTING 



PHYTOGEOGRAPHICAL 



PUBLICATIONS 



FOR SALE BY 



WILHELM 



M 



LEIPZIG 



■ ^ . ^ G L E R, Die pflanzengeograph ische 

 Gliederiing: Nordainerikas, erliiutertan der 

 nordamerikanischen Anlage des neuen 

 Koniglichen botanischen Gartens zu Dahlem- 

 bteglitz bei Berlin, Mit einer Verbrei- 

 tungskarte und einem Orientierungsplan. 

 gr.8. 1902. Price: M. 2.40. 



See Botanical Gazette, 1902, No. 4, 

 PP- 316, 317. 



A. Engler, Die Pflamen- Formation und 

 die Pflanzengeographische GHederutig der 

 Alpenkette, erlautert an der Alpenanlage des 

 neuen Kdniglichen botanischen Gartens zu 

 iJahlem-Steglitz bei Berlin. Mit 2 Orien- 

 t'erungskarten. gr. 8. 1901. Price: M. 2.40. 



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Folding Microscopes, new Doublet lens, for Nature 

 study, $3. Dissecting Microscope, new Doublet lens, 



for Nature study, $4- Complete Stu- 

 dent's Microscope reduced from $27.50 

 to $22. Beck's new $45 Laboratory 

 Microscope reduced to $36. 



Botanical Supplies—Dissecting in- 

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 presses, pocket magnifiers, etc. Project- 

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 coveringallsubjects. Agentsforall micro- 

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 Special prices to schixjis. Send for catalogue. 



Williams, Brown ^ *" 



Dept. 17 918 Chestnut Street, Philadelphia 



the Unlocrsiiy of CWcago Press 



Special printing facilities for academic \york. 

 including theses and repons of educational 

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 Educational and scientific w^ri^ printed in 

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Estimates furnished 

 t^he UivWersity of CHicago Press 



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