NATURAL HISTORY OF BRITISH FRESH-WATER LEECHES. 73
direct from springs is too cold. Little islands should be pro-
vided with plenty of peat so that the cocoons may be deposited
without the animals being disturbed. Various methods of
feeding were adopted. A favourite method was to drive into
the water poor worn-out horses, asses and mules. Later, more
healthy animals were used, and frequently changed. Less
repulsive methods were to place the leeches in small flannel
bags and take them to slaughter houses, where the bags and their
contents were placed in blood which had been defibrinated
by beating. The bags serve as points of support, without which
leeches are unable to suck. Another plan was to spread blood
on boards which were floated on the pond, and the attention of
the leeches was attracted by striking the surface of the water.
Some of the "farmers" fed their stock by throwing frogs and
newts into the water. We learn that the vaches require feeding
about once a year, medium sized leeches (moyennes) about twice
and the filets about three or four times. Food is given to the
leeches as soon as they emerge from their winter quarters.
Towards the breeding season (about June), feeding is discontinued
and is not resumed until September when the cocoon laying is
over.
The young leeches have many enemies, among which are
moles, shrews, voles, hedgehogs, ducks, storks and herons
Certain fish6 and aquatic larvae like Hydrophilus do a great
deal of damage. Their own kind also attack them, Horse-
leeches and Dutrochet's leech either cut them in two or swallow
them whole. Even the harmless snail leeches suck them when
young and tender.
Leech-farming does not seem to have been practised in England,
but in Ireland, in Co. Wexford, Lord Desart let a piece of marsh
land of about 40 acres to a company of Frenchmen for the
purpose of leech-culture (Simmonds, 40). The ponds were
prepared and the crops sown, but I have not been able to trace
the later development of this venture. Dr. Scharff (39), p. 193,
says : "I have never seen an Irish Medicinal Leech, and my
efforts to get a specimen have hitherto proved fruitless," but
O'Flaherty in his "West or H.-Jar Connaught" refers to them
(they are called dallog in Irish) as being common on the south
side of Lough Mask in 1684, and the late Sir W. Wilde stated
5 Mr. Blair tells me that he placed some young medicinal leeches with carp, expecting the
leeches to feed on the carp, but perversely the carp fed on the leeches.