LOOKING-GLASS. 
187 
ESSAY XXI. 
On Amphibious Animals. 
THIS clafs of animals, partaking of two natures, 
is lefs numerous than the laft j but, fmce they are not 
fo well known, it is our duty to mention fome parti- 
culars refpedting their exiftence. They are either 
naked, or covered with fcales ; being called amphi- 
bious, not becaufe they live alike on land or in 
water, but from the circumftance of their breathing 
at unequal intervals, and not regularly, as other 
creatures do. It is true, that they can exift for 
fome time in the air, but not under water fo long, 
without perifhing. Their blood is not warmer than 
that intermediate fpace which they fill. Ihus a 
touch of their cold bodies makes an unpleafant im- 
preffion, added to the horror that they infpire by 
their offenfive fmell, fuppofed poifon, and ghaftly 
figures. 
Some of them are four-footed, — fuch as the tor- 
toife, the toad, the frog, the cameleon, the fala- 
mander, the lizard, &c. 
Others have no feet, — fuch are vipers, ferpents, 
‘ adders, &c. Tortoifes are quiet, mild, and cool, 
being feemingly affected by no ftrong paffions. 
Spallanzani 
