three. 
STRUCTURE OF MAMMALS. 559) 
box of the monkey as compared with that of the lemur, and 
of apes as compared with monkeys, while in man the brain 
capacity is twice that of the highest apes. 
‘The different regions of the vertebral column are better: 
defined than in the birds and reptiles; this is seen in the- 
cervical vertebre, the number of which is usually seven. 
The exceptions to this rule are few, there being six in one: 
sloth (Cholepus), eight or nine in another sloth (Bradypus), 
and six in the American manatee. Behind the cervical is. 
the dorsal region, consisting of from ten to twenty-four, 
usually thirteen, vertebre, and the lumbar region, which is 
composed of from two to nine, usually six or seven, vertebra, 
and is marked off by the absence of movable ribs. ‘The 
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Fig. 484.—Skull of the Lion.—After Owen. 
shoulder-girdle is not solidly united to the dorsal vertebre, 
but loosely attached by mr les and tendons. The pelvis 
—1i.e., that portion called the ilium—connects with a single, 
sometimes two, rarely three, vertebrz of the sacral region, 
and the union of these vertebree with one or more caudal 
vertebra forms an assemblage of consolidated vertebrae, called 
the os sacrum, which in the sloths, or Edentates, comprises 
eight or nine vertebre. The number of caudal vertebre 
in the monkeys may amount to thirty, in the long-tailed 
manis (Fig. 501) to forty,* while in other mammals there 
may be less than this number, there being four retained by 
man and the larger apes, while in some bats there are only 
The coracoid bone is free in Monotremes. 
*In Microgale longicauda there are 48 ; in Manis macrura, 49. 
