474 
The Natural Ilistomj of British Grasses. 
all of them have even sent up many culms for a second crop, and 
all show a large quantity of aftermath. 
Nos. 5 and 6 have nearly disappeared. 
We see from these data that, in as far as yield and permanency 
are concerned, Nos. 2, 3, and 4 may be used advantageously : 
No. 2 is considerably earlier than 3 and 4, which in some cases 
may be much in its favour. From these circumstances I am 
induced to think that these grasses would be well worthy a trial 
on a greater scale than has yet been accorded them in artificial 
pastures. 
Diseases of Grasses. — Under this head it seems desirable to 
point out some of those affections of a fungoid form to which 
grasses seem more particularly liable : those which more com- 
monly attack cereals have been explained before the Society by 
!Mr. Sydney in his usual felicitous manner, under the names of 
Hed Rvhin, Mildeio, Smut, and Bent, with others of this class, 
all of which are more or less common to the grass tribe in ge- 
neral, though perhaps not to so great an extent in the wild grasses 
as in the cereals. 
The smut ( Uredo segetuni) is constantly found attacking the 
grass-flowers, but oftener, perhaps, on the flowers oi Arrlienathe- 
rum avenaceum than on any other species. I have seen whole 
patches of this grass covered with the black efflorescence of the 
fungus ; here, however, as the object is not grain, it produces but 
little mischief, though the attacked grass is always stunted in its 
growth. 
The greatest mischief done by fungi to grasses is that occa- 
sioned by the agaric, or mushroom tribe ; and more especially by 
those which form the circles in meadows, known as fairy rings. 
These often make a turf look very dissightly ; and though it has 
been said that they manure the grass, as evidenced from the 
circle of greener grass where they have decayed, yet we must 
remember that this ring of green is always surrounded by another 
of brown, withered herbage, consisting of nearly dead grasses ; 
and, indeed, it is in the decay of these that the phosphatic salts 
which Professor Way has shown to exist so abundantly in this 
tribe of fungi, are supplied. 
It may be here stated, that the fungus upon which the Pro- 
fessor experimented, and upon which his paper was founded, is 
the Afjariciis prunuhis, a plant which is abundant in all poor 
upland pastDres in Gloucestershire, and consequently the fairy- 
rings which are formed by them are at all seasons of the year a 
good criterion of the value of a field. This fungus is remarkable 
for growing in the month of May, on which account it can be 
distinguished from its congeners, as other fairy-ring agarics do 
