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Holmes—A Study in the Anatomy of 
and distribution of the vessels and tracheides. Since part of the wood 
consists of elements serving a mechanical purpose only, it is clear that an 
increase in the proportion of this part, in any regions of the shoot requiring 
extra support, will result in a decrease in the proportion of the other parts; 
that is, without disturbing the necessary amount of total conductivity, such 
a condition will decrease the specific conductivity. From this point of view 
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Fig. r. 
I have examined a number of similar shoots, to discover the variation in the 
proportion of water-conducting elements in the wood, by observations on 
their size and distribution ; and in this way to provide data for an anatomical 
explanation of the variation in specific conductivity. 
Material. For this investigation the material selected consisted of 
stool shoots of the hazel in their first year of growth. It is well known that 
the shoots which spring up from a stool in the first year after coppicing are 
