OE TORI, Se Ne Rete 
Oe Riva (Pine eee vy ar 
Notes and News. 475 
‘the production of oxygen by the organism caused a long and most 
interesting literary debate between him and Hoppe-Seyler. Traube 
was unable to devote more than a part of his time to investigations, 
peste the half and even to pass out through the cork layer. On 
ich roots, as on those grown in plaster casts, no hairs develop, which 
is probably due to the resistance of the medium. . The passage made 
net on the penetration of potato tubers by rhizomes of Cy f 
% Dactylon may be explained on other grounds than the excretion of a 
_ fothe inner. So the ability and the force needed to penetrate, living 
tissues is not peculiar to the specialized roots of Cuscuta, but 1s pos 
EFFER HAS demonstrated that it is the root alone which acs 
stotropic sensitiveness. “Al! previous investigations have be 
: y 
Sta the t h oan r 
ate of things is easily demonstrated, since the rays of 
as 
* Stimulus can be easily directed to a single point alone 
bend of the tube, and pushes on as far as the ot 
Whe e by heat geotropic © D enscibetuty, 
2 that | the tip of the root is not placed in the nicola ip directed 
