SCIENCE-ADVERTISEMENTS 



Marine Biological Laboratory 



Woods Hole, Mass. 



INVESTIGATION 



Entire Year 



INSTRUCTION 



July 3 to August 13, 

 1918 



Facilities £or rescach in Zoology, 

 Embiyology, Physiology and Bot- 

 &xiy. Seventy-six privato labora- 

 tories, $100 each for not over three 

 months. Thirty tables are avail- 

 able for beginners in research who 

 desire to work under the direction 

 of members of the staff. The fee 

 Cor such a table is $50.00. 



Courses of laboratory instiuction 

 with lectures are offered in Inverte- 

 brate Zoology, Embryology, Physi- 

 ology and Morphology and Taxo- 

 nomy of the Algae. Each course 

 requires the full time of the student. 

 Fee, $50. A lecture course on the 

 Philosophical Aspects of Biology 

 and Allied Sciences is also offered. 



SUPPLY Animals and plants, preserved, liv- 



*^»«« . nrr<«>T^».Tf«« i ug, and in embryonic stages. Pre- 

 DEPARTMENT served material of all types of 



_ , «? . V animals and of Algae, Fungi, Liver- 



Open the Entire Year worts and Mosses furnished for 

 classwork, oi for the museum. Liv- 

 ing mateiial furnished in season 

 as ordered. Price lists of Zoological 

 and Botanical materia 1 sent on ap- 

 plication. State which la desired. 

 For price lists and all information 

 regarding material, address 



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



The annua ] aimouncement will be sent on application to The 

 Director, Marine Biological Laboratory, Woods Hole, Mass. 



TEACHERS WANTED 



We have a steady demand for men in all depart- 

 ments of Science for Agricultural Colleges, and Uni- 

 versities. Special terms. Address 



THE INTERSTATE TEACHERS' AGENCY 

 Macheca Building; New Orleani, La- 



The Micro-scope 



12th Edition, Published April 10, 1917 



Re-Written and largely Re-IIIustratad 



Br SIMON HENRY GAGE of Cornell Unirereltr 



Postpaid $3.00 



COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



SCIENCE 



A K'EEKLY JOURNAL DEVOTED TO THE 

 ADVANCEMENT OF SCIENCE 



Entered in ihc poit-o£cc at Lancasto-, Pa., ai second daa mattel 



'Published every Friday; 



THE SCIENCE PRESS 



LANCASTER, PA. GARRISON, N. Y. 



SUB-STATION 84: NEW YORK 



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