KODAK FINISHING 



IVe Guarantee to get the best possible results from your 



exposures. Mail orders attended to promptly. 



Catalogue and Price List Free 



The Smith Sporting Goods Company 



TUCSON, ARIZONA 



LETTERING SHEETS 



We offer a series of six sheets of letters, figures, words, and symbols for the lettering 

 of diagrams and drawings for line cut reproduction. 



The lettering is in bold type in two sizes, and in italics. The sheets are Dennison's 

 best quality white gummed paper. A wealth of words and abbreviations relative to time, 

 weights, measures, climate, and experimental results, as well as chemical symbols, abbrevi- 

 ations used in morphology, etc., will give these sheets a wide utility. 



Sample on request 



Per sheet 10c Set of 6 sheets 50c Six sets $2.00 



THE PLANT WORLD TUCSON, ARIZONA 



LARGE AUTO-IRRIGATORS 



For the automatic watering of large pots or beds of soil we offer an Auto- 

 Irrigator Cup which is similar to the ordinary Atmometer in its form and 

 proportions, but is 14 inches in length and IJ inches in diameter. These 

 large cups are installed and operated in the same manner as the smaller 

 Auto-Irrigators which are now in general use, and also lend themselves 

 to various other purposes. 



Directions for the use of Auto-Irrigators will be sent on request. 

 THE PLANT WORLD - - Tucson, Arizona 



EFFICIENCY 



The Principles of Scientific Shop Management are Applied by us to the 



Printing Business 



We manufabture this Journal. In addition we produce 25 other scientific and teohnlcai 



publications and a large number of books and catalogues. 



All are bandied on a dtfiniti lehtduU maintaining the highest standard of meehanloal 



workmanship. 



WAVERLY PRESS 



WILLIAMS & WILKINS COMPANY 2419-3431 Greenmount Ave., Baltimore. Md., U. S. A. 



