256 MR. W. H. BURRELL ON THE iECIDIUM ELATINUM IN NORFOLK. 
the tree at Upper Sheringharu that T felt sure the mystery was 
solved. 
Before dealing further with the subject of this note, it will not 
be out of place to make a few statements concerning (a) Witches 
brooms in general, and (b) the family to which the specific fungus 
of the Silver Fir broom belongs. 
Witches brooms are found on a number of trees, including Beech, 
Fir, Pine, Larch, Birch, Hornbeam, Bullace, Cherry, and are a sign 
of disease ; they are the external evidence of parasitic fungi which 
form perennating mycelia in the tissues of the host. These parasites 
have a stimulating effect, causing enlargement of individual cells 
in the affected region, and the formation of abnormal tissues. 
Kerner’s description is so graphic that I cannot do better than quote 
him ; he selects the growth on Silver Fir as the type, and says : 
“ It always grows on one of the horizontally projecting lateral 
branches of the Fir, and raises its erect or curved twigs from the 
upper side, resembling, as it were, an epiphyte growing on the bark 
of the horizontal bough. The twigs are grouped in whorls, and 
not in two rows as usually happens in the lateral shoots of the 
Silver Fir. They are all shortened and thickened, and remarkably 
soft and pliable, because the cortical parenchyma has become spongy 
and the wood is only slightly developed. The buds, which in 
healthy tissues are egg-shaped, are almost spherical here. As in 
other instances of hypertrophied plant-members we have a precocious 
development, a so called ‘ prolepsis’ in these Witches brooms. The 
buds swell earlier and unfold earlier than those of healthy twigs. 
The leaves remain short, yellow, somewhat crumpled, and fall off 
when a year old, while those of normal twigs are long, linear, 
straight, dark green on the upper side, and remain in position from 
G — 8 years. The growth of the twig is restricted ; it dies off in 
a few years, and then inserted on the dark green branches of the 
Silver Fir remain the dry bristling brooms, whose appearance has 
stimulated the imagination of the peasantry, and given rise to the 
superstition as their name testifies * * * * * that their origin was 
connected with witches.” 
JEcidium elatinum , the cause of Witches brooms on Silver Fir, 
belongs to the UredineEe. As you are aware, all the members of 
this family are parasites, living in the tissues of phanerogams and 
ferns. Plowright names over three hundred and sixty host plants, 
