AND ITS CONSEQUENCES. 21 



explorations of many years over a wide area, I have detected 

 none other equally low in the system ; nor have I ascertained 

 than any brother-explorer in the same field has been more 

 fortunate. It is, up to the present time, the most ancient 

 Scotch witness of the great class of fishes that can in this case 

 be brought into court ; nay, it is in all probability the oldest 

 ganoid witness the world has yet produced ; for there appears 

 no certain trace of this order of fishes in the great Silurian 

 system which lies underneath, and in which, so far as geolo- 

 gists yet know, organic existence first began. How, then, 

 on the two relevant points — bulk and organization — does it 

 answer to the demands of the development hypothesis % Was 

 it a mere foetus of the finny tribe, of minute size, and imper- 

 fect, embryonic faculty ? Or was it of at least the ordinary 

 bulk, and, for its class, of the average organization % May I 

 solicit the forbearance of the non-geological reader should 

 my reply to these apparently simple questions seem unneces- 

 sarily proliy. and elaborate ? Peculiar opportunities of obser- 

 vation, and the possession of a set of unique fossils, enable 

 me to submit to our palaeontologists a certain amount of in- 

 formation regarding this ancient ganoid, which they will deem 

 at once interesting and new ; and the bearing of my state- 

 ments on the general argument will, I trust, become apparent 

 as I proceed. 



(See prefatory remarks.) A description of Ceplialaspis, as that which 

 now seems to be the most ancient vertebrate witness the world has yet 

 produced, is subjoined in Appendix, C. The A sterolepis appears to havs 

 the advantage over its predecessors only in point of bulk.] 



