BULLETIN 
OF THE 
TORREY BOTANICAL CLUB 
FEBRUARY, 1918 
On the constancy of cell shape in leaves of varying shape 
LILLIAN A. TENOPYR 
(WITH ONE TEXT FIGURE) 
INTRODUCTION 
Since the publication of Sanio’s observations on the size of the 
wood cells of Pinus sylvestris, the subject has aroused considerable 
interest, as is shown by the work of Amelung, Sachs, Strasburger, 
Gates, Keeble, Neilson Jones, Jakushkine and Wawilow, and Sierp. 
Among the zoologists who have investigated the same problem are 
Gaule, Donaldson, Hardesty, Levi, Morgan, Driesch, Rabl, Cham- 
bers, Popof, Berezewski, Jennings, and Conklin. 
Sanio (1872) shows that in the Scotch pine, the wood cells 
attain a definite (final) size, which is constant for the following 
annual rings. He finds, however, that the size of the wood cells 
does vary according to the height at which they are situated in the 
stem. The size of the wood cells increases as the stem is ascended, 
until a maximum is reached, then decreases toward the apex. The 
branches always have smaller wood cells than the main stem at 
the level at which the branch arose; but branches which arise from 
that portion of the main stem which had the largest wood cells, 
have also larger wood cells than the branches situated higher or 
lower on the stem. 
Amelung (1893) studied cell size in its relation to the size of 
the organ. He raised the question whether differences in the size 
of homologous organs within a species are accompanied by corres- 
[The BuLLetin for January (45: I-50) was issued February 8, 1918] 
51 
