6i 
SOME NOTES ON THE NATURAL HISTORY 
OF BRITISH FRESH WATER LEECHES: 
WITH RECORDS OF THEIR OCCURRENCE IN 
ESSEX. 
With Plates VI. ami VII. 
By HENRY WHITEHEAD, B.Sc. 
[Read 28th October 1911.] 
I N 1911 a very important paper, entitled “ A Revision 
of the British Leeches,” by Mr. W. A. Harding, was pub¬ 
lished in Parasitology. Previous to the appearance of this paper, 
the most recent work dealing with British leeches was John¬ 
ston’s Catalogue of the British Non-parasitical Worms in the 
Collection of the British Museum, published in 1865. 1 
Mr. Harding’s paper gives full descriptions of all the known 
British species with lists of synonyms. It contains an extensive 
bibliography and is well illustrated by coloured plates and 
figures. With such an admirable work in existence, some 
explanation seems necessary for the appearance of this paper. 
Few members of the Club have an opportunity of consulting 
the work mentioned, 2 and therefore the writer proposes to give 
a brief description of each species, emphasizing only those 
features by which specimens may be recognized. A number 
of observations on the life-histories and habits of these animals 
are scattered through the scientific periodicals of this and other 
countries, but these observations do not appear to have been 
brought together. An attempt is being made in this paper to> 
do so and to add to this material a few notes made by the writer 
whilst collecting and studying Leeches during the past two 
years. 
Folk-lore and early references to Leeches. —Leeches are 
referred to in very early writings, but unfortunately the species 
were hopelessly confused, and therefore the observations are of 
little scientific value. 
Probably the earliest reference to Leeches is in Proverbs 
xxx., 15. “ The horseleach hath two daughters, crying, Give ! 
Give ! ” The word translated as horseleech in this passage 
has been the subject of much discussion. The original Hebrew 
word was Aluka (Halucah or Gnaluka) and this was translated by 
X An account of the Irish fresh-water leeches by Dr. R. F. Scharff is given in the Irish 
Satinaltsl, vol. vii.. (1898) pp. 188-194. 
2 A copy has been kindly presented to the Library of the Club by Mr. Harding — Ed 
F 
