STATE HORTICULTURAL SOCIETY. 143 



to grow away from, aiul the priiiiar\^ roots to grow towards, the 

 earth's center, has long heen a sul)jeot of curious research. The 

 best information we have upon tlie matter is that these parts of 

 phmts are inherently endowed with the ability of using the action 

 of gravitation as a guide and of directing their cause of growth 

 thereby. Gravitation, as a force, certainly does not produce the 

 results. At the divergence of two roads a traveler may be forcibly 

 carried by an unmanageable horse in one of the two directions, or he 

 may leisurely consult a finger-board placed there for the purpose, 

 and delil)erately move in one of the ways. We cannot say the plant 

 ici/ls which way to go, but its action in relation to light and gravita- 

 tion resembles the latter, not the former part of our illustration. 



T have been careful to say ''leading stems" and "primary 

 roots"' above, for secondary branches of stems and roots behave dif- 

 ferently. Secondary roots make their way more or less in a hori- 

 zontal direction, and branches from them seem to have no power 

 whatever to direct their course by gravitation as a guide. It is 

 worth while, however, to mention that when a vigorous ])rimary root 

 is killed at its lower end, a secondary branch usually assumes the 

 properties of a primary and takes the place of the latter, just as a 

 .side branch of a tree may become the leader when the latter is de- 

 stroyed. 



Roots are also sensitive to touch, and bend this way or that in 

 a most wonderful manner in consequence thereof. If we cause a 

 grain of corn to germinate in a moist chamber in such manner that 

 the young root may be free to move, it will, as heretofore stated and 

 as ail know, bend downward; and if simply surrounded on all sides 

 by moist air, will grow in a vertically downward direction. If, how- 

 ever, we now touch one side of the tip with some adhesive substance 

 like a thick solution of shellac, and attach therewith a little disk of 

 paper or other solid substance, after awhile it will be noticed that 

 the root bends to the side oi)posite the foreign body. Farther, if we 

 fasten in a similar way a bit of thick paper on one side, and upon 

 the other thin paper of the same size, the root moves away from the 

 heavier object, thus in some sense recognizing the difference between 

 them — surely a most marvelous phenomenon! But the marvel does 

 not end here. Let it he understood that the cemented substance is 

 placed on the side of the very tip of the root. Here only will the 

 result follow. i3ut the actual bending of the root occurs at some 

 distance ('say an inchj above or away from the tip. There must 

 therefore be some communicaticni of the sensation, or whatever we 

 may call it, from the tip to this bending part. We know that sensa- 

 tions are carried along the nerves of animals, but there is something 

 of similar im]iort c.irried through tissues without nerves or anything 

 like them, and movements ordered and produced as a conse([uence. 

 We need not stop to .speculate, '' Do roots feel? " But we may open 

 our understanding to the fact that vegetable life is not very far re- 



