26 HIRUDO. 
While at North Berwick, several years ago, I was informed that a 
small pool on the summit of a rocky islet, Craigleith, at some distance 
from the shore, abounded in the Medicinal Leech. Having obtained be- 
tween twenty and thirty specimens, dwelling among thickish mud, all 
proved on examination, to be the Horse Leech. They were rather under 
middle size, none exceeding three inches in length, when animated by 
the heat, for, although taken in the month of July, they were almost 
torpid. 
About the same proportion of the Horse Leech may be taken from 
under stones on the margin of a lake, as found in the water. 
Parte IIT. 
Fic. 1. Hirudo sangwisuga, The Horse Leech ; back. 
2. Belly. 
3. Young specimen subsequently becoming green; back. 
4. Belly. 
5. Head with ocular specks. 
6. Variety? back. 
7. Head with ocular specks. 
8. Variety? quiescent. 
9. The same in motion. 
10, The same enlarged. 
§ 6. Hirupo mepicinatis—The Medicinal Leech.*—Plate II. fig. 11. 
Perhaps no animal of the known universe has contributed more to 
alleviate the sufferings of mankind than the Medicinal Leech. Hence 
its utility as the principal remedy in many distempers has been high 
and permanent. 
* Mr Brightwell, an accomplished naturalist, observes, that the Medicinal Leech is 
found occasionally in the neighbourhood of Norwich. Also that a dealer in leeches residing 
in Norwich, keeps a stock of about 50,000 in two large tanks of water floored with soft 
clay, wherein the animals burrow. Many capsules were found by Mr Brightwell deposited 
by the leeches in the tanks, which the owner had always neglected or destroyed from igno- 
rance of their nature.—Brightwell on Hirudo geometrica, and some other species of British 
Fresh-Water Leeches, Annals and Mag. of Nat. Hist., v. ix. p. 13. 
