332 GEOLOGICAL RELATIONS OF THE ROCK SYSTEMS 



it improbable that a wide geological interval occurred between the 

 consolidation of the fossiliferous beds which underlie the coal, and the 

 deposition of the coal measures themselves ; that there is no real con- 

 nexion between them — but that they belong to widely different geologi- 

 cal systems, the former referable to the base of the carboniferous system, 

 the latter fo the oolitic, and neither shewing the slightest tendency to a 

 confusion of type." 



This it must be remembered was merely a speculation based upon a 

 cabinet examination of the fossils. I presume similar reasonings have in- 

 fluenced more recent writers who have unhesitatingly referred these plants 

 (as it appears to me on very unsound evidence) to the oolitic epoch, (a) 



Let us then consider in a little more detail what this evidence is. 

 And first as to the physical evidence. Jukes, writing in 1850, (three 

 years after the publication of McCoy's valuable papers) and doubtless 

 havino* the view therein expressed in his mind, says thus. — " Some per- 

 sons have been struck with the oolitic aspect of the fossil plants collected 

 in New South Wales, (as also of those of India,j and have been led to 

 imagine, in consequence, that they did not belong to the same formation 

 as that in which the Productse, Spiriferse, &c above named, are found. 

 All the physical characters and relations of the rocks, however, both in 

 New South Wales, and Tasmania, led me to look upon the whole series 

 as one great continuous formation, and Mr. Clarke has since distinctly 

 informed me that he has obtained the same Spiriferse, Productse, &c. from 

 beds above those which contain the fossil plants, as are found in the 



beds below." 



" The perfect conformability and apparent passage from one group into 

 the other* would of itself render highly improbable any such difference 

 of age between the higher and lower beds as exists between any 



(a) De Zigno. Flora Fossilis Formationis Ooliticse. Unfortunately the introduction to 

 this most valuable and beautifully illustrated work has not yet appeared, so that we do not 

 know the author's reasons for considering these Australian and Indian plants oolitic. 



