18.01.2013 Views

The Descent of Man

The Descent of Man

The Descent of Man

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

pologie,' 1872; 'La Constitution des vertebres<br />

caudales.') that the tail in all quadrupeds consists<br />

<strong>of</strong> two portions, generally separated<br />

abruptly from each other; the basal portion<br />

consists <strong>of</strong> vertebrae, more or less perfectly<br />

channelled and furnished with apophyses like<br />

ordinary vertebrae; whereas those <strong>of</strong> the terminal<br />

portion are not channelled, are almost<br />

smooth, and scarcely resemble true vertebrae.<br />

A tail, though not externally visible, is really<br />

present in man and the anthropomorphous<br />

apes, and is constructed on exactly the same<br />

pattern in both. In the terminal portion the vertabrae,<br />

constituting the os coccyx, are quite rudimentary,<br />

being much reduced in size and<br />

number. In the basal portion, the vertebrae are<br />

likewise few, are united firmly together, and<br />

are arrested in development; but they have<br />

been rendered much broader and flatter than<br />

the corresponding vertebrae in the tails <strong>of</strong> other<br />

animals: they constitute what Broca calls the<br />

accessory sacral vertebrae. <strong>The</strong>se are <strong>of</strong> func-

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!