288 MICROSCOPY FOR BEGINNERS. 



The seeds, however, are usually on sale by the micro- 

 scopical dealers. To see the spirals, cut off a small 

 piece of the outer coating of the seed, place it in a shal- 

 low cell with a thin cover above it. Arrange the slide 

 on the stage, focus the objective, and while looking 

 through the instrument allow a drop of water to run 

 into the cell and around the object. Immediately the 

 spiral vessels will seem to be springing and growing out 

 of the seed in a remarkable way. They are adherent by 

 means of a mucilaginous substance, soluble in water, and 

 at the touch of the drop which dissolves their bonds 

 they are set free, to the astonishment of the observer 

 who sees them for the first time. 



19. EQUISETUM SPORES (Equisetum arvense) are worth 

 collecting and examining as transparent dry objects. 

 The plant is often called " Horse - tail " or " Scouring- 

 rush," and is to be found almost everywhere in sterile 

 places, especially along the railroad. The spores are 

 small, almost spherical, and have four long narrow fila- 

 ments which, when moistened, curl and curve arid twist, 

 and toss the spores about in every direction by what 

 has been styled a " quadrupedal hornpipe." If a quan- 

 tity of them is placed on a slide and gently breathed 

 upon, the moisture of the breath will set those four long 

 threads into motion, and the dance will at once begin. 

 One of my friends makes a permanent mount of these 

 curious spores by forming a cell of a single strand of 

 gold -lace fringe, and of course covering them with a 

 thin glass, fastened on with shellac cement, but so as not 



