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THE SCIENCE PRESS 

 Lancaster, Pa. Garrison, N. Y. 



NEW YORK : Sub-Station 84 



THE BULLETIN— For bargains in Ethnolograph- 

 ioal and Pre-historic Specimens. Books on Natural 

 History, Science, Travel, Voyages, ete. See The 

 Bulletin post free for 3 cent stamp. 



TENTH EDITION. 



the; microscope, 



an introduction to Microscopic Methods and to Histology, 

 by Simon Hknby Gage, of Cornell University. Over 

 360 large octavo pages and above 250 figures in this new 

 and fully revisededition. Price $2.00, postpaid. 

 COMSTOCK PUBLISHING CO., Ithaca, N. Y. 



Reptiles, Amphibians 

 and Fishes 



W. F. H. ROSENBERG, 

 57, Haverstock Hill, London, N. W., 



begs to announce the publication of a new Price List 

 (No. 15) of Reptiles, Batrachians and Fishes contain- 

 ing over 400 species from all parts of the World. This 

 Catalogue is conveniently arranged for reference, 

 with authors' names and indications of localities. It 

 will be sent post free on application as will the 

 following lists : 



So. 11, Birds' Skins, (5,000 species); No. 12, Le- 

 ppidotera, (5,000 species) ; No. 13, Coleoptera ; No. 

 1L Mammals; No. 15, Birds' Eggs. Also list of Cabi- 

 nets, Collecting Apparatus, etc. 



Largest stoek in the world of specimens in all 

 branches of Zoology. 



University of Colorado 



Mountain Laboratory 



Fourth summer session June 24 to Au- 

 gust 2, 1912. Courses in Field Biology 

 (animal and plant), Ecology, Systematic 

 Botany, Biology of Ponds and Streams. 

 Suitable work for undergraduates and grad- 

 uates. Daily Field excursions. 



The laboratory is at Tolland, Colo., in 

 the Rocky Mountains at an altitude of 

 8,889 feet. Climate cool and healthful. 

 Fees and expenses moderate. 



For pamphlet address the professor m 

 charge 



Dr. Francis Ramaley 



University of Colorado 



Pi* 



BOULDER 



COLORADO 



