14 f) 
MEGATHERIUM. 
I^eaver and other Rodeiitia,* supplied the 
^ss that was continually going on at the crown, 
tie constant addition of new matter at the 
anH purpose remained hollow, 
' . ” , ^ during the whole life of the 
the m!. possible to find any apparatus in 
more powerful engine for masticating roots than 
was formed by these teeth of the Megatherium • 
accompanied also by a property, which is the’ 
perfection of all machinery, namely, that of 
m,,., .laming itself perpetually in pe,Lt order 
> the act ol performing its M-ork. 
J^oiver Jaw. 
Phe loM'er jaw tPl 1 a ^ ■ 
'velglity in p.t,ni„ ^ tL'r ? ^ 
object of this she being to aff„,.d deep soete^ 
the -t. t.us or 
ti-. edk and 
«ame principle as the cutting^edo-e of 
plate of hard enamel is aonhed ifn “ 
■''“'•y of these teeth in^he si ^he 
"hge of the chisel and id v^ r . ‘^“tth.g 
^g-nst an inner p^eiVo" -l^e! 
"maintains its cuttiL crl constructed 
®ct of workino- against th"^ ” continually sharp, by the 
‘ceth opposed^to k ®‘"t''arly constructed extremity of the 
t Pi r .s. 
“'S this p^ul|,‘^'’ '■'^P''c«c‘Hs the section of the cavity contain- 
