Cuar. XIII.] LEECHES. 483 
the march of troops in the mountains, when the Kan- 
dyans were in rebellion, in 1818, the soldiers, and 
especially the Madras sepoys, with the pioneers and 
coolies, suffered so severely from this cause that numbers 
perished.! 
One circumstance regarding these land leeches is re- 
markable and unexplained; they are helpless without 
moisture, andin the hills where they abound at all other 
times, they entirely disappear during long droughts ; — 
yet re-appear instantaneously on the very first fall of 
rain; and in spots previously parched, where not one 
was visible an hour before, a single shower is sufficient 
to reproduce them in thousands, lurking beneath the 
decaying leaves, or striding with rapid movements 
across the gravel. Whence do they re-appear? Do 
they, too, take a “summer sleep,” like the reptiles, 
molluscs, and tank fishes? or may they, like the Roti- 
Jera, be dried up and preserved for an indefinite period, 
resuming their vital activity on the mere recurrence of 
moisture ? ? 
Besides a species of the medicinal leech, which * is 
1 Davy's Ceylon, p. 104; Mar- Europe; the four anterior ones 
SHALL’S Ceylon, p. 10. 
> See an account of the Rotif ra 
and their faculty of repeated vivi- 
faction, in the note appended to 
this chapter. 
8 Hirudo  sanguisorba. The 
paddi-field leech of Ceylon, used 
for surgical purposes, has the 
dorsal surface ot blackish olive. 
with several longitudinal stria,more 
or less defined; the crenated 
margin yellow. The ventral sur- 
face is fulvous, bordered laterally 
with olive: the extreme margin 
yellow. The eyes are ranged as 
in the common medicinal leech of 
rather larger than the others. The 
teeth are 140 in each series, ap- 
pearing as a single row; in size 
oe a 
tA 
Seid: 
a 
Du: 8-I, VEN1T Ral, 
diminishing gradually from one 
end, very close set. and about half 
ihe width of a tooth apart. When 
tull grown, these leeches are about 
Ir2 
