680 PKOCEEDINGS OF THE GEOLOGICAL SOCIETY. 



chersee, HoloptycMus in the Upper Devonian of North Devon, and 

 Coccosteus in the Middle Devonian of the Eifel, to say nothing of 

 the association of nnmerons species of fish with marine Mollusca, 

 Corals, &c. associated together in the same beds in the Yaldai Hills 

 &c., where Cejplialaspis and eight or nine other genera occur, having 

 species identical with our own Scottish Old Red Sandstone, and 16 

 species of shells common to our Devonian also*. Thus, then, 

 we have some grounds for placing our marine Devonian rocks on 

 the same horizon as, and contemporaneous with, the recognized divi- 

 sions of the Old Red Sandstone in other localities ; but the physical 

 structure and succession, as exhibited in North Devon alone, is (and 

 was years ago) enough to establish this. 



To the Devonian series therefore we assign the 329 species pecu- 

 liarly Devonian, after ehminating the 56 which are common to that 

 formation and to the Carboniferous ; and it is only through the Upper 

 •Devonian beds that a close agreement takes place between the species 

 of the two groups of rocks, where 45 of the bQ (or 383) pass to the 

 Carboniferous, 25 from the Middle to the Carboniferous, and only 3 

 species are common to the Lower or Lynton group and the Carbo- 

 niferous beds f. (Table X.) 



But I cannot admit (as stated), because I have failed to detect, 

 that a single form occurs in common between the Silurian and Car- 

 boniferous, although they are said to be thus related through the 

 species Stropliomena rhomboidalis, by Professor Jukes, loc. cit. 



We must in this case adhere to circumstances and facts as we find 

 them, and receive the opinions and decision of experienced palseonto^ 

 legists until contradicted. 



I have contended, aided by the stratigraphical position of the 

 rocks, for the intermediate zoological grouping and value of the forms 

 of life in the Devonian as related to the Silurian through the Trilo- 

 bites, and notably and distinctly by the individuahty of certain well- 

 marked genera not known out of the Devonian series, either in 

 Britain or over all Europe : nor are they known below in the Silu- 

 rian rocks, or above in the Carboniferous in any area. 



The Middle group, which holds so distinct a place in the series in 

 North and South Devon, both by richness in special and peculiar 

 genera, and in number of species, is paralleled in every particular in 



* Mr. W. H. Baily, Palgeontologist to the Geological Survey of Ireland, at the 

 Bath Meeting of the British Association, 1865, communicated to the Geological 

 Section the first notice of the occiu-rence of fish in the Old Red Sandstone of 

 the Bristol area ; these remains he obtained from the base of a conglomei-ate bed 

 exposed in the cliff at Portishead, and a^so from red flaggy beds on the shore 

 between liigh- and low-water mark. He identified the scales as those "of 

 Holo'^tyclims nobilissimus and Glyptolepis elegans,'^ associated with plants and 

 bones, and also what appeared to be " the fin-rays of a fish like Glyjptolepis, or 

 Platygnathus, in Yellow Sandstone." These beds would probably represent the 

 upper part of the Old Bed Sandstone. The paucity of fish-remains in any por- 

 tion of the Old Bed of this area enhances the importance of this communica- 

 tion, and may yet aid us in determining their position in the series of the Portis- 

 head rocks : a fragment of a scale ornamented like those of Bothriolepis or As- 

 terolepis was also found. 



t Two of which are doubtful, if not all. 



