A CRITICISM ON PROF. OWEN'S THEORY. 563 



us doubt the possibility of all such interpretations. The question 

 which naturally arises is, whether by proceeding after this fashion, 

 groups of bones might not be arranged into endless typical forms. 

 If, when a given element was not in its place, we were at liberty to 

 consider it as suppressed, or connate with some neighbouring element, 

 or removed to some more or less distant position ; if, on finding a 

 bone in excess, we might consider it, now as part of the dermo- 

 skeleton, now as part of the splanchno-skeleton, now as transplanted 

 from its typical position, now as resulting from vegetative repetition, 

 and now as a bone Ideologically compound (for these last two are 

 intrinsically different, though often used by Professor Owen as 

 equivalents) ; if, in other cases, a bone might be regarded as 

 spurious (p. 91), or again as having usurped the place of another; 

 if, we say, these various liberties were allowed us, we should 

 not despair of reconciling the facts with various diagrammatic 

 types besides that adopted by Professor Owen. 



When, in 1851, we attended a course of Professor Owen's lec- 

 tures on Comparative Osteology, beginning though we did in the at- 

 titude of discipleship, our scepticism grew as we listened, and reached 

 its climax when we came to the skull ; the reduction of which to the 

 vertebrate structure, reminded us very much of the interpretation 

 of prophecy. The delivery, at the Royal Society, of the Croonian 

 Lecture for 1858, in which Prof essor Huxley, confirming the state- 

 ments of several German anatomists, has shown that the facts of 

 embryology do not countenance Professor Owen's views respecting 

 the formation of the cranium, has induced us to reconsider the verte- 

 bral theory as a whole. Closer examination of Professor Owen's 

 doctrines, as set forth in his works, has certainly not removed the 

 scepticism generated years ago by his lectures. On the contrary, 

 that scepticism has deepened into disbelief. Andweventure to think 

 that the evidence above cited shows this disbelief to be warranted. 



There remains the question What general views are we to 

 take respecting the vertebrate structure ? If the hypothesis of an 

 " ideal typical vertebra " is not justified by the facts, how are we 

 to understand that degree of similarity which vertebrae display ? 



We believe the explanation is not far to seek. All that our 

 space will here allow, is a brief indication of what seems to us the 

 natural view of the matter. 



Professor Owen, in common with other comparative anatomists, 

 regards the divergences of individual vertebrae from the average 

 form, as due to adaptive modifications. If here one vertebral ele- 

 ment is largely developed, while elsewhere it is small if now the 

 form, now the position, now the degree of coalescence, of a given 

 part varies ; it is that the local requirements have involved this 

 change. The entire teaching of comparative osteology implies that 



