CHAP. VII.] 



LEECHES. 



305 



to degenerate into ulcers, which may lead to the loss of limb 

 or even of life. Both Marshall and Davy mention, that 

 during the march of troops in the mountains, when the 

 Kandyans 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 of 

 them perished. 1 



One circumstance regarding these land leeches is re- 

 markable ad unexplained ; they are helpless without 

 moisture, and in 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 Rotifera, 

 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 2 is 



1 DAVY'S Ceylon, p. 104 ; MAR- 

 SHALL'S Ceylon, p. 15. 



2 Hinulo aanguisorba. The paddi- 

 field leech of Ceylon, used for sur- 

 gical purposes, has the dorsal sur- 

 face of blackish olive, with several 

 longitudinal strife, more or less de- 

 fined ; the crenated margin yellow. 

 The ventral surface is fulvous, bor- 

 dered laterally with olive ; the ex- 

 treme margin yellow. The eyes are 



DORSAL. VENTRAL. 



ranged as in the common medicinal 

 VOL. I. X 



leech of Europe ; the four anterior ones 

 rather larger than the others. The 

 teeth are 140 in each series, appearing 

 as a single row ; in size diminishing 

 gradually from one end, very close 

 set, and about half the width of a 

 tooth apart. When full grown, these 

 leeches are about two inches long, 

 but reaching to six inches when ex- 

 tended. Mr. Thwaites, to whom I 

 am indebted for these particulars, 

 adds that he saw in a tank at Kolona 

 Korle leeches which appeared to him 

 flatter and of a darker colour than 

 those described above, but that he 

 had not an opportunity of examining 

 them particularly. 



Mr. Thwaites states that there is a 

 smaller tank leech of an olive-green 

 colour, with some indistinct longi- 

 tudinal striae on the upper surface ; 



