6 FIRST BOOK OF GRASSES 



of what it is like; it is something hke Poa pratensis. 

 Some common names, especially those of trees, 

 indicate the kind: Oak, with black, white, scarlet, 

 swamp, and post oak, for example, and also hickory 

 and ash; but for herbs, and especially grasses, the 

 common name usually gives no indication of the 

 kind of plant it refers to. Often the name is mis- 

 leading. Rib-grass is not a grass, but a plantain; 

 poison ivy is not an ivy, but a sumach. To convey 

 definite ideas we must use definite terms and definite 

 names. 



TOOLS NEEDED 



Any work that one engages in requires tools. For 

 the study of grasses we need but few. Grass flowers 

 are too small to be seen distinctly with the naked 

 eye. A lens magnifying about ten diameters is 

 necessary. This may be mounted on a stand or it 

 may be a hand lens. A simple dissecting microscope 

 with two or three lenses of different magnification 

 would be more convenient and would well repay the 

 cost, but it is not absolutely necessary. If one has 

 only a hand lens, an eye-piece, such as watchmakers 

 place in the eye, will also be found very useful in dis- 

 secting, as it leaves both hands free. One or two 

 dissecting needles are needed. These can be made 

 by forcing the heads of coarse sewing needles into 

 a pencil-shaped piece of soft wood. After some prac- 

 tice one learns to use the nail of the left forefinger 

 skilfully in dissecting. One can work more rapidly 



