222 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. 



Grit contains the same forms. The Lower Coal-measures yield the 

 same, with the addition of B. navicula, B. Oldhamii, and B. 

 Dumontii ; none occur in the Upper Coal-measures — this order, 

 like all others in the Carboniferous series, dying out at its close, not 

 to appear again. 



The genera Bucania of Hall and EupJiemus of M'Coy are synony- 

 mous with Bellerophon. Ireland has yielded 21 species of Bellero- 

 phon, Scotland 15, England 17, Belgium 25, and America 39 species ; 

 only 19 species range through Europe, 8 of them being British ; and 

 14 of these 19 are Eussian. 



Cephalopoda. — No fewer than 169 species are distributed through 

 the British Carboniferous system. 4 genera and 6 species occur in 

 the Calciferous or Tuedian beds, 5 genera and 22 species in the Lower 

 Limestone Shale, 8 genera and 140 species in the Carboniferous Lime- 

 stone ; 5 genera and 33 species are Yoredale ; 3 genera and 30 species 

 are Millstone Grit ; 3 genera and 24 species occur in the Lower Coal- 

 measures, 3 genera and 6 species in the Middle Coal-measures, and 

 1 genus and 2 species in the Upper Coal-measures. These 169 species 

 represent 8 genera — Actinoceras 1 species, Cyrtoceras 3, Discites 17 

 (subgenus of Nautilus), Goniatites 59, Nautilus 36, Orthoceras 48, 

 JPoterioceras 3, and Trigonoceras 2 species. 



The accompanying Table of the 8 British genera shows the number 

 of species in each country, including, as in the two prior Tables, 

 Belgium and America for comparison, in which it will be seen that 

 the 169 species, through the 500 occurrences, are thus distributed : — 

 the number of species in the 8 genera in England is 126, in Scot- 

 land 63, in Ireland 107, and in Belgium 90. Comparison carried 

 beyond Europe to America, as before, shows generic affinity through 

 114 species, hardly a single form being British. All Europe, only 

 yields 95 species through 11 areas ; research and the accident of our 

 possessing these rocks highly developed is the reason why our mol- 

 luscan fauna is so extensive. 





England. 



Scotland. 



| Ireland. 



Belgium. 



America. 



Appearances. 





1 



1 



1 



1 



2 



6 





2 



3 





8 



5 



18 





10 



3 



14 



4 



1 



32 





59 



15 



32 



25 



32 



163 





18 



14 



21 



22 



54 



129 





33 



24 



36 



29 



20 



142 





2 



3 



2 







7 





1 





1 



"i 





3 





126 



63 



107 



90 



114 



500 



