The evolution of man : a popular exposition of the principal points of human ontogeny and phylogeny . o under-stand how it can be merely the modified anterior portion ofthe vertebral column. It is a complex, capacious bonystructure, consisting of no less than twenty bones, differing widely in form and size. Seven ofthese skull-bones constitute thespacious case which encloses thebrain, and in which we distinguishthe strong, massive floor of the skull(basis cranii) below, and theboldly arched roof of the skull(fornix cranii) above. The otherthirteen bones form the facialskull, which especially p
The evolution of man : a popular exposition of the principal points of human ontogeny and phylogeny . o under-stand how it can be merely the modified anterior portion ofthe vertebral column. It is a complex, capacious bonystructure, consisting of no less than twenty bones, differing widely in form and size. Seven ofthese skull-bones constitute thespacious case which encloses thebrain, and in which we distinguishthe strong, massive floor of the skull(basis cranii) below, and theboldly arched roof of the skull(fornix cranii) above. The otherthirteen bones form the facialskull, which especially provides the bony envelopes ofthe higher sense-organs, and at the same time as the jaw-skeleton, encircles the entrance to the intestinal lower jaw (usually regarded as the twenty-firstskull-bone) is jointed to the skull-floor, and behind this,embedded in the roots of the tongue, we find the tongue-bone, which, like the lower jaw, has originated from thegill-arches, together with a portion of the lower arch, whichoriginally developed as skull-ribs from the ventral sideof the Fig. 264.—Human skull,from the right side. VERTEBRAL THEORY OF THE SKULL. 293 Although, therefore, the developed skull of the higherVertebrates, in its peculiar form, its very considerable size,and its complex structure, seems to have nothing incommon with ordinary vertebrae, yet the old comparativeanatomists at the close of the eighteenth century correctlybelieved that the skull is originally merely a series ofmodified vertebra?. In 1790, Goethe picked up out of thesand of the Jews burying-ground among the downs nearVenice, a dismembered skull of a sheep; he at once per-ceived that the face bones (like the three vertebrae of theback of the skull) are also derivable from vertebrae. And,in 1806, Oken (without knowing of Goethes discovery), atIlsenstein, on the way to the Brocken, found a beautifullybleached skull of a hind; the thought flashed through him,It is a vertebral column ! 1
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