Crossland: Fungus Foray at Grassington, etc. 399 
plants is large and varied. Many uncommon species have been, 
and are, found within its boundaries. This led us to expect a 
variety of plant diseases caused by parasitic fungi, nor were we 
altogether disappointed. Fifteen species were seen; their 
names, along with those of their host plants, are given in the 
list of species which will be found in the ‘Transactions of the 
Yorkshire Naturalists Union,’ No. 33, shortly to appear. The 
great abundance of Xenodochus carbonarius on Potertum offictnale 
was most striking. A far more lamentable feature was the 
sycamore leaf blotch. Nearly all the sycamore trees in Grass 
Woods were affected by this unsightly ‘parasite’ Rhytesma 
acertnum. We never saw the disease so prevalent anywhere. 
It prevails, more or less, in all the districts visited. It is even 
in some of the forest-tree nurseries, where one would least 
expect to find it. Here, at any rate, some attempt should be 
made to check it ; there may have been, but if so, unsuccessful. 
Seeing that the propagation spores of the disease do not ripen 
and germinate on the fallen leaves until spring, there is ample 
time to collect and burn all that are shed in the nursery area. 
When every leaf of a tree is attacked, besides making the tree 
look so repulsive, its timber producing powers are very much 
reduced ; it is utterly impossible for the leaves to perform their 
functions to the full when one fourth, or one third of their 
substance factories are choked up and destroyed by the thick, 
black scabs of this disease. 
The Mid. W. Division has been previously so well worked for 
its Uredinaceous plant diseases by Mr. West and the late Mr. 
Soppitt that, though we found no fewer than 26 species in the 
three localities, there are no additions to the Mid. W. Fungus 
Flora in this branch. 
Quite a number of small fry was found at the several places 
on decaying sticks and herbaceous plant remains. These are 
as-interesting as, and even more so than, the conspicuous kinds, 
but require more searching for. No fewer than 36 species of 
Discomycetes were met with; and 15 Myxomycetes, including 
Cribraria rufa, a new county record. While agarics were 
found in fairly great variety, considering past conditions, they 
were very sparing in quantity; just ones and twos here and 
there. The commonest and most abundant agaric was the 
strong smelling Hebeloma crustulintforme. Of the genus 
Mycena 15 were found, Cortinarius 11, Russula 12, and 
Hygrophorus tro. 
Two or three of the members revisited Grass Woods on the 
1907 November t. 
