Ilex Aquifolium, L., in Reference to Specific Conductivity. 535 
(C3, Ci, Ai) there is a flattening of the curve at the beginning of the 
leafy region of the stem, where the general tapering is influenced by the 
close succession of the petioles and the shortness of the internodes. The 
shoot A 3 has the lowest figure for wood-area (8-2 sq. mm. at the base). 
Among the holly twigs it should be noticed that in Shoot L the wood-area 
reaches 24 *6 sq. mm. at the base of the three-year-old shoot. In Shoot H 
it is only 14-9 sq. mm. at the base of the four-year-old shoot. 
Diagram IV. Internodes numbered from base to apex. , (Scale, 5 internodes = 1 cm.). 
Curve B (total cavity area in sq. mm.). This curve gives (as far as is 
possible from a consideration of transverse sections) a measure of the 
absolute conductivity of the wood — i. e. of the volume of water which it 
can transmit in any known period of time. Its direction is associated with 
that of Curve A, consequently there is a general descent from base to apex. 
There are peculiarities in the curves for the rhododendron shoots, different 
from those seen in holly. In the shoots of Rhododendron ponticum , in 
