16 
LECTURE VII. 
the brain. He observed also, that having cut 
off the heads of some, and opening the bodies 
twelve days afterwards, the motion of the heart 
was still perceptible ; so slowly is the vital prin- 
ciple discharged from these inactive animals. 
The most beautiful of all the Land Tortoises 
is the T. Geometrical or Geometrical Tortoise, 
so named from the elegantly regular variegations 
of its shell, which is very convex, and of a black 
colour, with each piece marked by several bright 
yellow stripes radiating from a common centre^ 
It is a native of many parts of Africa. 
A species much allied to the geometrical, 
but much larger, is what I have myself described 
under the name of T. radiata or the Radiated 
Tortoise. It measures more than a foot in length; 
is extremely convex, and nearly smooth, whereas 
the geometrica is remarkably tuberculated : the 
pattern is still more elaborately disposed than 
in the former, the rays or streaks being more 
numerous. It is a native of Madagascar, and 
as some say of America also. 
The largest of all the Land-Tortoises is a 
species now called the Indian Tortoise. T. In- 
dica. It was first described by Mons. Perrault, 
