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Bot Zeitung 1867 p 257

A de Bary Ueber den Krebs und die Hexenbesen der Weisstanne Abies pectinata

The Krebs consists of a lumpt on the stem or branches, the swelling is about twice the diameter of the stem above & below it. Remarkable for very thick bark which si enternally deeply cracked. Ulimately the bark comes off & the wood rots extensively. The wood and especially bark is covered with mycelium which is continued into the branches that grow out of the swellings & reproduces itself in the young leaves. The branches growing out of the swellings are the little upright trees or Hexenbesen. He speaks also of hexenbesen growing out of the stem (for Hexenbesen he quotes De Bary Ann Sc Nat 4 Ser Tom XX p 90). The fungus is Aecidium elatinum: he speaks fo the mycelium growing from swellings into "side branches" without producing reproductive organs, which latter are only on the true hexenbesen. The hexen besen is only formed where the mycelium grows from the swellings into a bud beginning to elongate

If it grows into already unfolded though still young shoots it does not produce a hexen besen, only another swelling one and The same swelling may proudce hexenbesen & normal branches Normal shoots free from mycel may come from hexen besen. The hexen besen are found all over the tree, most rarely at the summit of a young tree. The hexenbesen-shoots may either grow from the very first vertically up, or bend upwards with a bent piece. The first year they are simple shoots & from a winter bud at the top. The branches which grow from the main hexenbesen axis are like the primary branches of a young fir tree & grow out on all sides

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(2

Hexenbesen-

The leaves fall off in autumn & are rather smaller than normal, "krautartig-fleischig" & light yellow green in colour. If the fungus does not fructify which is very rare the leaves they live over the winter

The hexenbesen sists on the branches like a strange looking bush in winter bare, in summer light green" Imitating a little fir tree if it grows regularly or looking like a confused bush if it has grown irregularly. The hexen besen are usually more regular in growth when only one grows out of a swelling. They usually die in a few years but may live in one case 16 years

In the hexen besen, as in the swellings, the bark is very thick. / "Very rarely one finds side shoots on the hexenbesen free from mycelium which then assume all the properties of norma fir branches"

(I don't understand this as I thought the side branches of the hexenbesen were always like normal branches of a young fir tree. FD)

232v

Chapter on Radicles [Darwin's heading or title for this item]