THE MISTLETOE IN HEREFORDSHIRE. 865 
also give origin to bud-like processes, which, deepening in colour, grow 
up obliquely through the bark, and appear as little shoots in its chinks, 
soon developing leaves and stems as a “separate plant." Dr. Harley 
also gives good ground for believing the perpendicular roots penetrate 
the hard wood by their own growth, in the absorption they occasion in 
the wood itself, and in the depth to which they enter,—a conclusion 
which all who have made careful sections of the bough with the 
Mistletoe attached, will have no difficulty in believing. 
* When the roots of the Viscum album," says Dr. Harley again, 
* have become fairly infixed into the medullary system of nourishing 
plant, their outer portions become gradually thickened by the forma- 
tion of woody layers upon their surfaces. This increase in the lateral 
dimensions of the root takes place pari passu with that of the branch 
upon which it grows; for every layer of wood deposited on the branch, 
a corresponding one is deposited upon the Mistletoe; and the growth 
of the two plants proceeding thus uniformly, the concentric rings of ` 
the stock pass uninterruptedly into those of the Mistletoe, and the 
woody layers become coincident. Whilst the roots thus undergo in- 
crease and lignifieation about their outer portions, their inner ex- 
tremities which now lie deeply within the hard wood, constantly retain 
their original soft cellular condition; they are in fact to the Viscum, 
What the cellular rootlets of terrestrial plants are to them." 
II.—TREES UPON WHICH THE MISTLETOE GROWS IN 
HEREFORDSHIRE. 
. The trees upon which the Mistletoe grows, as far as I have ascer- 
tained, are as follows :— 
Apple-tree (Pyrus Malus domestica); Hawthorn (Crategus Oxyacantha) ; 
throughout the county. not uncommon 
Abele-tree or White M e (Populus Crab(Pyrus Malu p general through- 
alba); not co out the county. 
Grey Poplar (P. canescens) ; Lime-tree (Tilia Europea). 
Aspen (P. Tremu 2); “coin te pmi campestre). 
Black Poplar (P. nigra); rare. Whi veins Acacia (Robinia 
Black Italian Poplar (P. monilifera) ; i 
very freely. Mountdin Ash ure Aucuparia). 
aoe e r Canadensis) ; t (Fraxinus excelsior). 
mmon White Willow (Salix alba). 
Ontario » Poplar e. candicans); com- ona (Corylus — 
