20 THE PLANT WORLD. 



green on tlic upper side and a lighter green on the under side. 

 The leaf is very graceful when growing. 



At present the devil's tongue seems like a very useless plant but 

 perhaps it may become a useful one in later years through Mr. 

 Burbank's wonderful experiments. 



OF INTEREST TO TEACHERS. 

 Edited by Dr. C. Stuart Gager. 



As stated in the December Plant World, the U. S. Depart- 

 ment of Agriculture is distributing to schools and colleges for use 

 in teaching economic botany and commercial geography, samples 

 of plant fibers, which formed part of the fiber exhibit of the De- 

 partment at the Louisiana Purchase Exposition. 



Such a package, received lately at the Wadleigh High School, 

 New York City, contained samples of five kinds of fibers from 

 different parts of the world — cotton, sisal, Jaumave istle, hemp, 

 and flax. Each sam]:)le was plainly labeled with the common and 

 Latin name of the plant, together with a brief description of 

 the method of preparing the fiber, and its commercial uses. 



Accompanying the package was a very instructive illustrated 

 pamphlet by Mr. Lyster H. Dewey, Botanist in charge of In- 

 vestigations of Fiber Plants, Bureau of Plant Industry, entitled 

 " Principal Commercial Plant Fibers." The writer divides vege- 

 table fibers into three distinct classes: (i) The cottons, with soft, 

 lint-like fiber one-half inch to two inches long, composed of single 

 cells, borne on the seeds of different species of cotton plants. 

 (2) The soft fibers, or bast fibers, including flax, hemp, and jute; 

 flexible fibers of soft texture, ten to one hundred inches in length, 

 composed of man\- overlapping cells, and borne in the inner bark 

 of the plants. (3) The hard, or leaf, fibers, including manila, 

 sisal, mauritius, New Zealand fibers, and istle, all having rather 

 stifif, woody fibers one to ten feet long, composed of numerous 

 cells in bundles, borne in the tissues of the leaf or leaf stem. A 

 detailed description of the difl^erent fibers has the following in- 

 teresting introduction : 



