d watered all over; and the back of
a spade may now be used to make it still harder, as well as to plaster
the surface all over."[E] Mushrooms are cultivated very extensively by
Mr. Ingram, at Belvoir, without artificial spawn. There is a great
riding-house there, in which the litter is ground down by the horses'
feet into very small shreds. These are placed in a heap and turned
over once or twice during the season, when a large quantity of
excellent spawn is developed which, placed in asparagus beds or laid
under thin turf, produces admirable mushrooms, in the latter case as
clean as in our best pastures.[F]

Other species will sometimes be seen growing on mushroom-beds besides
the genuine mushroom, the spawn in such cases being probably
introduced with the materials employed. We have seen a pretty crisped
variety of _Agaricus dealbatus_ growing in profusion in such a place,
and devoured it accordingly. Sometimes the mushrooms will, when in an
unhealthy condition, be subject to the ravages of parasitic species of
mould, or perhaps of _Hypomyces_. _Xylaria vaporaria_ has, in more
than one instance, usurped the place of mushrooms. Mr. Berkeley has
received abundant specimens in the Sclerotioid state, which he
succeeded in developing in sand under a bell glass. Of course under
such conditions there is much loss. The little fairy-ring champignon
is an excellent and useful species, and it is a great pity that some
effort should not be made to procure it by cultivation. In Italy a
kind of _Polyporus_, unknown in this country, is obtained by watering
the _Pietra funghaia_, or fungus stone, a sort of tufa impregnated
with mycelium. The _Polypori_, it is said, take seven days to come to
perfection, and may be obtained from the foster mass, if properly
moistened, six times a year. There are specimens which were fully
developed in Mr. Lee's nursery at Kensington many years since. Another
fungus is obtained from the pollard head of the black poplar. Dr.
Badham says that it is usual to remove these heads at the latter end
of autumn, as soon as the vintage is over, and their marriage with the
vine is annulled; hundreds of such heads are then cut and transported
to different parts; they are abundantly watered during the first
month, and in a short time produce that truly delicious fungus
_Agaricus caudicinus_, which, during the autumn of the year, makes the
greatest show in the Italian market-places. These pollard blocks
continue to