xii.J TUB ORIGIN OF SPECIES. 281 



not uncommonly exhibit GO, 80, or even 94 per cent, 

 of genera in common with those whose remains arc 

 imbedded in their predecessor. Not only is this true, 

 but the subdivisions of each formation exhibit new 

 Bpecics characteristic of, and found only in, them ; and, 

 in many cases, as in the lias for example, the separate 

 beds of these subdivisions arc distinguished by well- 

 marked and peculiar forms of life. A section, a hundred 

 feet thick, will exhibit, at different heights, a dozen 

 species of ammonite, none of which passes beyond its 

 particular zone of limestone, or clay, into the zone below 

 it or into that above it ; so that those who adopt the 

 doctrine of special creation must be prepared to admit, 

 that at intervals of time, corresponding with the thickness 

 of these beds, the Creator thought fit to interfere with 

 the natural course of events for the purpose of making 

 a new ammonite. It is not easy to transplant oneself 

 into the frame of mind of those who can accept such a 

 conclusion as this, on any evidence short of absolute 

 demonstration ; and it is difficult to see what is to be 

 gained by so doing, since, as we have said, it is obvious 

 that such a view of the origin of living beings is utterly 

 opposed to the Hebrew cosmogony. Deserving no aid 

 from the powerful arm of bibliolatry, then, does the 

 received form of the hypothesis of special creation derive 

 any support from science or sound logic % Assuredly 

 not much. The arguments brought forward in its favour 

 all take one form : If species were not supcrnaturally 

 created, we cannot understand the facts x, or y, or z; 

 we cannot understand the structure of animals or plants, 

 unless we suppose they were contrived for special ends ; 

 we cannot understand the structure of the eye, except 

 by supposing it to have been made to see with ; we 

 cannot understand instincts, unless we suppose animals 

 to have been miraculouslv endowed with them. 



