138 SENSITIVENESS OP THE APEX CHAP. 711 



3 h. very slightly curved from the card ; after 24 h. tip curved 

 towards card. Kefixed new square laterally, alter 9h. distinctly 

 curved from the card, and after 24 h. curved at right angles frcm 

 the perpendicular and from the card. 



(24.) A rather large oblong piece of card fixed with shellac to 

 apex : after 24 h. no effect, but the card was found not to be 

 touching the apex. A small square was now refixed with 

 shellac ; after 16 h. slight deflection from the perpendicular 

 and from the card. After an additional day the radicle became 

 almost straight. 



( 25.) Square of card fixed laterally to apex of young radicle ; 

 after 9 h. deflection from the perpendicular considerable ; after 

 24 h. deflection reduced. Kefixed a fresh square with shellac : 

 after 24 h. deflection about 40 from the perpendicular and from 

 the card. 



(26.) A very small square of card fixed with shellac to apex of 

 young radicle : after 9 h. the deflection from the perpendicular 

 and from the card amounted to nearly a right angle ; after 24 h. 

 deflection much reduced ; after an additional 24 h. radicle almost 

 straight. 



(27.) Square of cai'd fixed with shellac to apex of young 

 radicle : after 9 h. deflection from the card and from the perpen- 

 dicular a right angle ; next morning quite straight. Kefixed 

 a square laterally with shellac ; after 9 h. a little deflection, 

 which after 24 h. increased to nearly 20 from the perpendicular 

 and from the card. 



(28.) Square of card fixed with shellac; after 9 h. some 

 deflection ; next morning the card dropped off; refixed it with 

 shellac; it again became loose and was refixed; and now on the 

 third trial the radicle was deflected after 14 h. at right angles 

 from the card. 



(29.) A small square of card was first fixed with thick gum- 

 water to the apex. It produced a slight effect but soon fell 

 off. A similar square was now affixed laterally with shellac : 

 after 9 h. the radicle was deflected nearly 45 from the perpen- 

 dicular and from the card. After 36 additional hours angle of 

 deflection reduced to about 30. 



(30.) A very small piece, less than ^th of an inch square, of 

 thin tin-foil fixed with shellac to the apex of a young radicle ; 

 after 24 h. no effect. Tin- foil removed, and a small square of 

 sanded card fixed with shellac; after 9h. deflection at nearlj 

 right angles from the perpei^dicular and from the card. Next 



