PECULIARITIES IN GRO^VTH OF HAWTHORN-TREE. 367 
passage, it struck me as describing what I had myself seen, and sub- 
sequent observations satisfied me of its general truth. I did not, 
however, for some time, pay special attention to the subject, or endea- 
vour to trace the causes which led to the mode of growth described by 
Mr. Jesse. Of late, however, from living in a' part of the country 
where old thorns abound, I have been induced to study their growth 
with some degree of care. 
During its early, and perhaps its middle life also, the Hawthorn 
follows the usual mode of growth amongst exogenous trees — the suc- 
cessive layers of wood being deposited pretty regularly around the 
stem, which, in consequence, maintains a nearly cylindrical form. As, 
however, the tree advances in age, it appears that the woody bundles 
cease to grow at certain definite points of their circumference, whilst 
they continue to grow freely at others. The result of this is, that ribs 
or columnar projections are formed upon the face of the stem^ to which 
they give an irregularly fluted appearance, the ribs, or flutings, having 
sometimes a vertical, sometimes a spiral direction. Tliis mode of 
growth is continued for many years, the ribs, or flutings, increasing 
most rapidly in a direction immediately outward from the centre of the 
stem, the intervening seams or channels becoming meanwhile more and 
more deep. After awhile the same thing happens to the ribs, or 
flutings, as had originally happened to the parent stem; growth goes 
forward at some points of their circumference, whilst it ceases at others, 
and thus each rib becomes itself subdivided into a number of secondary 
ribs, or flutings. As the tree reaches the period of old age, decay, 
commencing at the heart-wood, proceeds gradually outwards until the 
whole of the (original) cylindrical part of the stem is destroyed; and 
when this point is reached, all living communication is, of course, at 
an end between the several ribs or segmental portions of the stem. 
These — now distinct from each other, except just near the root — are 
often drawn more or le^s asunder by the combined w^eight of branches 
and foliage, and appear as so many separate stems. On the inner face 
of these stems is found, not bark, but the remains of the decayed 
heartwood ; but this inner face, once a portion of the original cylin- 
drical stem, bears so small a proportion to the whole circumference, 
that it may readily be overlooked; and w^as indeed overlooked by Mr. 
Jesse, because he describes the different stems as becoming regularly 
barked round. It was not until I had arrived at these conclusions 
