The Correlation of Growth under the 
Influence of Injuries. 
BY 
C. O. TOWNSEND. 
I T has been the purpose of the experiments which form 
the basis of this paper to determine in what time, 
through what distance, and to what extent an injury inflicted 
upon one part of a plant will influence the growth of the 
injured and of the uninjured parts. The experiments have 
been carried on in the Botanical Institute at Leipzig during 
the years 1896-7, under the direction of Professor Dr. Pfeffer, 
to whom I wish to express my sincere thanks for his 
invaluable suggestions, and also for the use of his splendidly 
equipped laboratory. 
The correlation of growth has received considerable 
attention from investigators either directly or indirectly, 
but the observations have been made for the most part 
under the influence either of long-continued irritation or of 
a series of irritations produced at more or less irregular 
intervals, and extending over a considerable period of time 1 . 
In the following experiments special attention has been 
given to first effects of injury upon the curve of growth, 
1 Pfeffer, Druck und Arbeitsleistung, 1893. Hering, Ueber Wachsthumscorre- 
lation in Folge mechanisclier Hemmung desWachsens; Pringsheim’s Jahrbuch, 
Vol. 29, p. 132, 1896. Kny, On Correlation in the Growth of Roots and Shoots ; 
Annals of Botany, Vol. viii, p. 265, 1894. 
[Annals of Botany, Vol. XI. No. XLIV. December, 1897.] 
Mm2 
