Hazel-zvood with Reference to Conductivity of Water . 555 
extremely vigorous; they attain a much greater length and thickness than 
the shoots borne on old branches of the tree, and they bear abnormally 
large leaves. While they exhibit great vigour in the direction of vegetative 
growth, they do not bear reproductive organs, no inflorescences being formed 
in the winter buds. In fact the stool shoots differ sufficiently from the tree 
shoots to be distinguished as a juvenile form. The rapid growth of these shoots 
and the large size of their leaves might suggest that they are provided with 
an unusually efficient water-conducting system, but it is clear from Professor 
Farmer’s experiments that the wood in stool shoots has on the average 
a lower specific conductivity than that shown by shoots taken from older 
parts of trees of the same species, 
while there is also a considerable 
and regular variation in specific 
conductivity in different regions 
of the same shoot. Anatomical 
investigation should indicate the 
extent and perhaps throw light 
on the cause of this variation. 
The four shoots investigated 
were cut on September 22, 1917, 
from separate stools in the same 
wood, coppiced the previous winter; 
they were measured, catalogued, 
and preserved in 70 per cent, 
alcohol. At this time in autumn 
the full number of internodes has 
been- formed, and the apex for the 
winter is determined; development 
in length and width is almost com¬ 
plete, but the free end of the shoot 
has not reached its ripened winter 
condition, and the leaves are still functional. In the hazel the more 
vigorous stool shoots reach a length of over 1 \ metres in their first season, 
and some of them branch from a few of the upper nodes. The particular 
shoots chosen were unbranched, and were all a metre or more in length, being 
composed of from twenty-four to twenty-nine internodes. The lengths of 
these and of the whole shoots respectively are compared in Fig. 1, from which 
it will be seen that the longest internodes occur in the lower middle part of 
each shoot. The leaves are largest in this region also; the largest leaf 
measured was 13 cm. long and 11-5 cm. wide. In September four or five of 
the nodes at the base of the shoot have lost their leaves. In most cases, 
but not in all, the true terminal bud aborts, and the apex of the shoot is 
occupied by a lateral bud. In one of the specimens examined, H8, the 
Fig. 2. 
