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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



nome gracilis appear to be all known in these lowest beds of the 

 northern Carboniferous rocks. 



Lower Limestone and Shales. — 13 genera and 26 species illustrate 

 these shaly limestones at the base of the Carboniferous ; the 3 

 chief genera are — Fenestella 12 species (far too numerous), Glau- 

 conome 3, and Pustulipora 2 species ; the remaining 9 genera have 

 only 1 species each ; many of these, necessarily, also occur in the 

 succeeding Carboniferous Limestone. 



Carboniferous Limestone. — 72 species occur, belonging to 19 

 genera; the most important of the latter are — Fenestella with 

 25 species, Glauconome 8, Polypora 8, Rhabdomeson 3, Pustulipora 

 4, and Ceriopora 5 species. The 13 remaining genera, although 

 poor in species, are highly characteristic ; amongst them may be 

 named Sulcoretepora, Synocladia, Vincularia, Actinostoma, and Dias- 

 topora. JSTo species passes to higher strata or above the Carboni- 

 ferous Limestone. 



Arachnid a. — Only in the Lower Coal-measures have we detected 

 the Arachnida, 5 species representing 3 genera — Architarbus sub- 

 ovalis, H. Woodw., Eoplirynus Prestvicii, Busk, Eoscorpius anglicus, 

 H. Woodw., and E. carbonarius, Meek and Worth. ; an unde- 

 scribed form occurs, which, however, may be E. anglicus. E. carbo- 

 narius is also an American species, occurring in the Coal-measures 

 of Illinois ; and Architarbus is also a North-American form. The 

 occurrence of two of the three genera and one species in two 

 areas so widely separated is significant, with many other facts, of 

 the probability of the continuity of land between Britain and 

 America during the long period required for the deposition of the 

 Coal-measures and the accumulation of coal. 



Mtriopoda. — The 2 genera of Chilognathous Myriopoda, Eupho- 

 bena and Xylobius, which occur in our Coal-measures are also 

 American, and, with the Arachnida, again add strong presump- 

 tion to land-continuity, densely covered with that peculiar flora 

 known to have flourished during the Coal-measure period. We 

 possess 3 species of Euphoberia, viz. E. anthrax, Salt., E. Broivnii, 

 H. Woodw., and E. ferox, Salt. Dr. Dawson's genus Xylobius, also 

 the known American species " Sigillariat" lends additional interest 

 to the attempt to correlate our fauna and flora of the Coal-measures 

 with those of the American continent ; for many species of plants 

 are identical, and with them associated faunal groups. 



Insecta. — Both the Orthoptera and Coleoptera are represented in 

 our Coal-measures. The Mantidse through the genus Lithomantis 

 of Dr. H. Woodward, the Locustidas through Gryllacris, Swinton ; 

 these two genera belong to the Orthoptera. The genus Curculioides 

 of Dr. Buckland belongs to the Coleoptera. These all occur in our 

 Lower Coal-measures. Their history and zoological aflinities have 

 been ably described by Dr. H. Woodward, F.R.S., in the 'Journal' 

 of our Society (vol. xxxii.) ; doubtless every fresh investigation into 

 the rocks that hold and yield the extinct flora of our coal-fields will 

 bring to light the remains of the three last groups, the Arachnida, 

 Myriopoda, and Insecta; they are, or were, intimately associated 



