220 DUTROCHET'S LAND LEECH IN ESSEX.
pairs of eyes, but their number and position are subject to
variation.
Dutrochet's Leech was first observed in England in 1850,
in Regent's Park. Since that date numerous records of its
occurrence have been published, but its appearance has been
sporadic. In 1877 Mr. J. E. Harting ('Zoologist' Ser. 3. vol I.,
pp. 515-523) summarised the records of its occurrence in England.
From this we learn that it had been observed at Lyne, between
Dorking and Horsham, in 1869 ; at the Beddington Sewage Farm,
near Croydon, in 1870 ; and at Elstree, Herts, in 1876. Mr. F. J.
Bell ('Zoologist,' 1896, p. 264) records a large specimen from the
Thames near Maidenhead, taken that year. Mr. W. A. Harding
DUTROCHET'S land-leech, Trocheta subviridis.
(Kindly lent by the Publishers of the "Zoologist.")
in a paper on British Leeches ("Parasitology" vol. iii., 1910),
pp. 183-186) gives Capel, Surrey, as another locality, and states
that in 1909 it was observed at the Withington Sewage works,
near Manchester. Finally, the finding of two specimens in a
garden at Penge in February, 1911, is described in the
'Zoologist' for May of the current year (p. 155).
Mr. Harding is of the opinion that Dutrochet's Leech may
possibly be indigenous in this country. Up to the present
it has been found only in Italy, France and Algeria.
The particulars given with the above records show that the
specimens were found either in gardens on lawns, paths or under
boxes, or in streams contaminated with sewage—in all cases