PHYSICS. University of Kansas, Lawrence. Two half-time, graduate assistantships, at $600 or $700 according to to training, allowing about half of regular graduate work toward an advanced degree; or one full-time position, $1200 to $1400, allowing one-third of regular graduate work. Please state training and give references with application. WANTED Assistant Professor of Physics. Salary, around $2000, depending on the qualifications of the candidate. Applicants should state education and experience and special lines of endeavor; also, have one or more persons write directly to give information regarding the applicant's personality and qualifications. Address: A. W. Nye, University of Southern California, Los Angeles. University of Hawaii Teaching Fellowship in Biology, 1920-21 Applications will be received for appointment to a Teachiug Fellowship in Biology. Stipend of $750.00. Laboratory assistance not to exceed fifteen hours per week required. Field of research either in botany or zoology. New University laboratory for marine biology located at the Honolulu Aquarium will be opened this summer. Address applications to the President. Glassware Laboratory Apparatus Chemicals-Reagents in Stock for prompt de- Send us your list of require- What other dealers cannot Lenz Apparatus Co., Inc. Manufacturers—Importers-Exporters 18 EAST 16th STREET NEW YORK, N. Y. BACTERIOLOGIST: Ph.D., aged 39, desires change of location from a New England college to larger institution, to medical school or to public health laboratory work in West, middle West or South. Ten years of teaching general elementary bacteriology and advanced pathogenic bacteriology; also of supervising graduate study. Twelve years of research in bacteriological and immunological problems. Three years in charge of diagnostic laboratory work. Author of about sixty monograghs on bacteriological, immunological and protozoological subjects. Opportunity desired to combine teaching and research; or to establish or direct a public health laboratory. Address X, Care of SCIENCE, Garrison, N. Y. Naturalists' Supplies We carry a stock for prompt delivery I. Collecting Utensils. II. Breeding Apparatus and Cages for Living Animals. III. Preparing and Preserving Utensils. V. Magnifiers, Microscopes and Accessories. VI. Botanists' Supplies. VII. Explorers' and Collectors' Camp Outfits. VIII. Miscellaneous Naturalists' Supplies. IX. Oologists' Supplies. X. Aquaria. XI. Books and Publications. XII. Chemicals K-S Museum Cabinets of Glass and Metal New Illustrated Biological Catalogue will be sent free of charge upon application THE KNY-SCHEERER CORPORATION We have been handling Natural History Material of all kinds for the past fifty years, and so have accumulated a very complete stock. Our prices are as low as the quality of the specimens will permit. We are constantly preparing circulars and price lists covering our material in the different branches, which we will be pleased to send free of charge to the readers of Science. Some of our recent circulars: S-110 Complete Trilobites CONCHOLOGY GEOLOGY Cambridge, Mass. Care Peabody Museum, Mine Allee C. Metcher, n Heredity And Evolut. In By C. STUART GAGER Director Brooklyn Botanic Garden, Brooklyn, N. Y., Author of 113 Illustrations. 12mo, xv+265 Pages. Cloth, $1.25 Postpaid A CONCISE treatment suited to beginning students Contents in Brief: Life History of a Fern; Funda- P. BLAKISTON'S SON & CO., Publishers, PHILADELPHIA "The Science of Every Day" -The modern idea of physics Millikan and Gale's fits this definition admirably. GINN AND COMPANY |