2 ART. 6. — Y. YENDO : 



method to a plant so effectively as is done with animals. If we 

 should succeed, however, in making particular chemical substances 

 circulate in a certain measure through the body of plants, it might 

 be possible to stimulate their development or to cure them of 

 diseases, and moreover, to render them immune by the injection 

 of certain substances. 



The scope of the present study is to answer the following 

 questions : — 



1) Is it possible that a certain amount of a substance injected 

 into a certain part of the plant body, is conducted through the entire 

 plant ? In other words, how far and to what part is an injected 

 solution conducted during a definite time ? 



2) How does the effect of injection differ according to the 

 kinds of plants, organs and tissues ? 



The present investigation was carried out at the suggestion 

 and under the guidance of Peof. M. Miyoshi, during the academic 

 year of 1911-12 in the Botanical Institute of the College of 

 Science, Imperial University of Tokyo. I beg here to express my 

 gratitude to him for his generous assistance and advice. 



II. Method of injection. 



A medical syringe, provided with measured shaft and 1.5 c.cm. 

 in volume, was employed. Usually the injection was made by 

 inserting the cannula into the plant body deej^ly and obliquely, 

 until it touched a vascular bundle ; in the case of injecting into a 

 hard tissue of a plant, a slit was made with a knife and then 

 the syringe was applied. 



We have to ascertain into what parts the injected solutioii 

 penetrates and how far the fluid reaches. On injecting a coloured 

 solution I observed that it enters the air- containing intercellular 



