W. A. Harding 
175 
of Hirudiniculture the curious reader is referred to the comprehensive 
monograph of Ebrard (1857). 
Leech farming was never practised in this country, although ac¬ 
cording to Johnson (1816) and Dalyell (1853) “ leech-gathering ” 
appears to have been a not uncommon and somewhat remunerative 
calling in the earlier part of the last century. In Ireland Thompson 
(1856, p. 427) states that, in 1849, the medicinal leech (for which the 
Irish name was dallog ) was still found in pools in the neighbourhood of 
Lough Mask and that “ in summer the leech-gatherers sat with their 
legs in the water on which the creatures fasten and are thus obtained.” 
The indigenous supply was supplemented by large importations of 
leeches from abroad. In 1816 we employed “at least one hundred 
foreign leeches for every British leech ” (Johnson). Brightwell, in 1842, 
refers to a dealer in Norwich who kept a stock of about 50,000 leeches 
in two large tanks. At this time leeches were imported in large sacks, 
sometimes but not always packed in damp grass, and the resulting 
mortality among them was very great. 
Not infrequently consignments of the medicinal leech were adul¬ 
terated with quantities of the innocuous horse-leech. 
Hirudo niedicinalis is not the only leech which has been used in 
phlebotomy. Hirudo troctina (Johnson, 1816), occurring in North 
Africa and in Southern Europe, where it is perhaps an introduced 
species, was largely imported at one time for medical uses. 
The characteristic ocelli on the dorsal surface of the latter species 
earned for it in England the name of “ trout leech ” whilst the fact that 
large numbers were imported from Algiers, together with the supposed 
resemblance of its dorsal pattern to the uniform of a French dragoon, 
led to the name of “ le dragon d’Alger ” by which it was known to the 
foreign trade. 
Several other species have been used for blood-letting in different 
countries. Limnatis ( Poecilobdella) granulosa in India, Hciementaria 
officinalis in Mexico, Hirudo nipponia in Japan (Whitman) and Macro- 
bdella decora in the United States (Yerrill) are or have been used in 
phlebotomy. 
Varieties. A large number of colour-varieties of Hirudo niedicinalis 
have been described. For descriptions and coloured illustrations of 
these the reader is referred to the works of Brandt and Ratzeburg (1829), 
Moquin-Tandon (1846) and particularly to the monograph of Ebrard 
(1857). 
