24 



Again, if it is an insignificant member of the oolite series in one 

 respect, in another it is of considerab'e value. Professor Phillips 

 says of it, " Though so unimportant a rock in other respects, it is 

 probably more continuous and more uniform in character from 

 Dorsetshire to the Humber than any other member of the oolite 

 formation, except the sands of the inferior oolite." (Manual, p. 300). 

 These two landmarks, then one at the top, the other at the bottom 

 of the Bath oolite are of great use in determining the sequence of 

 beds in particular localities. 



Again, if its fossils are generally in poor condition they have a 

 peculiar interest of their own. First of all I would remind you of a 

 circumstance to which our Secretary was, I believe, the first to call 

 attention. He pointed out that its fossils have far more affinity to 

 those of the inferior than to those of the great oolite, which lies 

 between them. Of 71 Gloucestershire species, 45 were found to be 

 common to the inferior oolite. Of course, we can easily conceive it 

 possible that a series of forms of life in some particular locality, 

 having been obliged to emigrate through a change of surrounding 

 conditions, might, if the disturbing influences were removed, return 

 to their former quarters. This is what Professor Buckman believes 

 to be the case here, and, if so, it is a case which is almost, if not 

 quite, unique, In chemical composition the Cornbrash is certainly 

 more akin to the inferior than to the great oolite. I would not 

 venture to say of the fossils that the assertion so ingeniously made 

 about them is quite as proven as the place of the beds in geological 

 sequence ; and I am inclined to agree with Professor Phillips, who 

 used always to tell his classes about some beds on the top of Shot- 

 over, that it was well that some geological problems should remain 

 as open questions, because then every young student would have an 

 opportunity of trying his " prentice hand " and head in suggesting a 

 solution of the riddle. 



Again, if the Cornbrash is of small thickness, the number of 

 fossils it contains is comparatively large. I have already mentioned 

 that Professor Buckman's paper in 1857 gives 71 species from Glou- 

 cestershire. He adds some details about the Cephalopods and 

 J'rachiopods, and promises in a future paper to give us a complete 

 list. AVliitravos in |si;o .u'a \ < a list of 7'* s])c<-ics from thr neigh- 

 bourhood of Oxt'urd : whilst Livkriiby rolle-i-trd as many as \ '',() 

 from a thin but ru-h bed not more than live IVrt tliirk at Scar- 



