8 Dr. SuaAw's Remarks on 
quently not fo long. On the contrary, the e/eéfrica may be always 
preferved in this manner at leaft a month, and frequently two or 
three months together, without feeming to lofe much of its vigour; 
nay, it may even be kept pretty clofely confined between two glafles 
for many days without any danger of perifhing. 
Another very curious particular belonging to the Sc. elec- 
trica (and which cannot be obferved in the other fpecies) is, that 
if cut in two about the middle, both parts will live and appear vi- 
gorous for a very confiderable time; fometimes a fortnight; but 
with this very extraordinary circumftance, that the tail-part always 
furvives the head-part two or three days; fo that the principle of 
vitality is much more powerful in the lower part of the creature 
than in the upper. 
"This experiment I made and bd repeated feveral years ago, 
and till lately imagined that it had not been obferved by any other 
perfon; but I lately obferved a remark by Haller in his Bibliotheca 
Anatomica, that the circumftance of both the cut parts living has 
been mentioned in a German work entitled Unzer’s Kleine. Scbrifien. 
This being a work I have never feen, I can only quote the very 
brief expreffion of Haller, viz. ‘ Scolopendræ. diffeétz utraque 
* medietas yixit:” yet there is no mention of the pofterior part 
furviving the anterior, nor is the particular fpecies of the infect 
mentioned, ; 
I am aware that it may be objected to the idea of thefe two forts 
of Scolopendra being fpecifically different, that the different habita- 
tion of the animal, and a difference in colour, are not fufficient to 
conftitute a difference of fpecies, efpecially as fome animals are 
fuppofed to refide in habitations of the greateft poffible difference; 
the Fa/ciola hepatica for inftance, which is fuppofed to inhabit the 
waters, and yet is found in great abundance and in great vigour 
jn the liver and gall-bladder of íheep. It is alfo a well-known 
circum- 
