152 LIFE OF PROFESSOR HUXLEY chap, x 



two contributions in 1858 — one on the general subject of 

 the cell theory, the other on the particular question of the 

 development of the skull. " In a striking ' Review of the 

 Cell Theory,' " says Sir M. Foster, " which appeared in the 

 British and Foreign Medical Review in 1858, a paper which 

 more than one young physiologist at the time read with 

 delight, and which even to-day may be studied with no 

 little profit, he, in this subject as in others, drove the sword 

 of rational inquiry through the heart of conceptions, meta- 

 physical and transcendental, but dominant." 



Of this article Professor E. Ray Lankester also writes : — 



. . . Indeed it is a fundamental study in morphology. The 

 extreme interest and importance of the views put forward in 

 that article may be judged of by the fact that although it is 

 forty years since it was published, and although our knowledge 

 of cell structure has made immense progress during those forty 

 years, yet the main contention of that article, viz. that cells are 

 not the cause but the result of organisation — in fact, are, as he 

 says, to the tide of life what the line of shells and weeds on the 

 sea-shore is to the tide of the living sea — is even now being re- 

 asserted, and in a slightly modified form is by very many cytolo- 

 gists admitted as having more truth in it than the opposed view 

 and its later outcomes, to the effect that the cell is the unit of 

 life in which and through which alone living matter manifests 

 its activities. 



The second was his Croonian Lecture of 1858, " On the 

 Theory of the Vertebrate Skull," in which he demonstrated 

 from the embryological researches of Rathke and others, 

 that after the first step the whole course of development 

 in the segments of the skull proceeded on different lines 

 from that of the vertebral column ; and that Oken's imagi- 

 native theory of the skull as modified vertebrae, logically 

 complete down to a strict parallel between the subsidiary 

 head-bones and the limbs attached to the spine, outran 

 the facts of a definite structure common to all vertebrates 

 which he had observed.* 



* " Following up Rathke, he strove to substitute for the then domi- 

 nant fantastic doctrines of the homologies of the cranial elements ad- 

 vocated by Owen, sounder views based on embryological evidence. 



