SCIENCE-ADVERTISEMENTS 



KARPINSKI, BENEDICT and 

 CALHOUN'S 



Unified Mathematics 



A combination text in College Algetra, 

 Trigonometry and Analytic Geometry 



Along the Right Line 



Dean John R. Allen, University of Minne- 

 sota: " I think the book is along the right 

 line, and that Mathematics of the future will 

 develop along this line, especially for engi- 



Better than the Old Way 



Professor J. H. Tanner, Cornell University: 

 "It seems to me that a student who has care- 

 fully worked his way through this book will 

 have a far better grasp of the subject of ele- 

 mentary mathematics than one who has 

 studied the separate parts in the old way, and 

 that he will also be able to use it far more 

 effectively as a tool in his later work." 



Cloth. 529 pages. $2.80 



D. C. HEATH & COMPANY 



Boston New York Chicago 



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OF AMERICA 

 HOME OFFICE, NEWARK, N. J. 



Forrest F. Dryden, President 

 Incorporated Under the Laws of Uie Stale of New Jersey 



Marine Biological Laboratory 



Woods Hole, Mass. 



INVESTIGATION 



Eatire Year 



INSTRUCTION 



July 2 to Angaot 12, 

 1919 



SUPPLY 



DEPARTMENT 



Open the Entire Year 



Facilitiea for reseach in Zoology. 

 Embiyology, Physiology and Bot- 

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 for such a table is 350.00. 



Courses of laboratory instruction 

 with lectures are offered in Inverte- 

 brate Zoology, Protoaoology Em- 

 bryology, Physiology and Morph- 

 ology and Taxonomy of the Algae. 

 Each course requires the full time 

 of the student. Fee,S50. Alecture 

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 also offered. 



Animals and plants, preserved, liv- 

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 served material of all types of 

 animals and of Algae, Fungi, Liver- 

 worts and Mosses furnished for 

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 ordered. Microscopic slidesin Zool- 

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 Botanical material and Micioscopic 

 Slides sent on application. State 

 which iadesired. For price lists and 

 alii nformation regarding material, 



GEO. M. GRAY Curator, Woods Hole, Masa. 

 The annual annoimcement will be sent on application to The 

 Director, Marine Biological Laboratory, "Woods Hole, Mass. 



Th© Mioro-soope 



12th Edition, Published AprillO, 1917 



Rc-Wrltten and largely Re-Illustratad 



By SIMON HENRY GAGE of CoTnell Univeraity 



Postpaid $3.00 



COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



■WANTED 



Audubon's Birds of America 



7 Volumes Octavo Edition 



Please state condition of binding and if all the plates 

 are complete in the set. Address 



FREDERICK C. HARRIS 



Box 2244 BOSTON, MASS. 



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3 Webster Terrace NEW ROCHELLE, N. Y. 



