186G.] DUMCAX — I^FEl-LIAS COEALS OP SOriH WALES. 27 



This coral-fauna is eyideiitly on a lower geological horizon than 

 that of the Sutton Stone and of irocastle, but its species have the same 

 general facies as those of the Infra-has of England and France ; and 

 the TJiecosrmlice and Montivaltke of the zone oi Ammonites Jloreanus 

 and of the "W^elsh beds are the representatives of the branching and 

 simple corals of the coral-zone of Lombardy. It is interesting to 

 find that the ILadreporaria abound at the base and at the upper part 

 of the Infra-liassic series, that they do not appear to be associated 

 with Ammonites, except rarely, and that as a whole the coral-fauna 

 of the Infra-lias is more distinct from that of the true Lower Lias 

 than the coral-fauna of any one of the Oolitic beds is from that of 

 another. 



The species are numerous, and the specimens whence they were 

 determined are, generally speaking, plentiful ; but they do not indi- 

 cate such a vigorous growth as is now noticed in the troj)ics. The 

 branching forms associated with solitary forms and small caliced 

 compound Astraeans denote a warm-temperate climate, and both 

 deep water and a neighbouring shallow sea — that is to say, if the 

 present coral-fauna can be reasonably compared with those of the 

 past. 



The ^adreporaria ^of the Infra-lias are distributed as species in 

 the following manner : — 



Brocastle, Ewenny, Cowbridge, Sec., Sutton and Southern down, ] ^ -i^ecie-^ 



Marton, Lincolnshire, Skye J ^^ 



Am'monitcs-angulatus zone in France and Duchy of Luxembourg... 16 species. 



Am7nonites-])lanorbis zone, England and France &c 4 species. 



White Lias 3 species. 



Azzarola beds 10 species. 



Avicula-contorta beds. (British) 1 species. 



Two of the species of the Ammonites-^lanorhis zone {Montlivaltia 

 Haimei audits varieties, diR()iSeiDtastrcmFromenteiA) pass upwards and 

 are found at barton ; and five species from the iox^igii A.-angidatus 

 zone are found in South Wales. Three Triassic species ascend to 

 the Sutton Stone. 



There would thus appear to be 39 species peculiar to the British 

 Infra-liassic coral-fauna. 



9. Conclusion. — It would appear, from the facts and opinions sub- 

 mitted in this communication, that the fossilii'erous beds of Sutton, 

 Southerndown, Brocastle, and Ewenny contain so many species of 

 Madi'eporaria that they become important members of the series 

 which, being placed between the Keuper and the Lias containing 

 Ammonites BucJclandi, has been named the Infua-lias, that the 

 Mollusca and certain well-known species of ]^adreporaria which are 

 grouped together at Brocastle have similar relations to each other in 

 the Calcaire de Yalogne, in the zone of Ammonites Moreanus of the 

 Cote d"Or, in the A.-angidatus zone of the east of France, and in the 

 Gres de Luxembourg, and that the above-mentioned beds in Wales 

 constituting a coraUiferous horizon are the equivalents of the upper 

 beds of the French and Luxembourgian Infra-has ; that the Aladi'e- 

 poraria of the zone oi Ammonites planorhis in England and those of 



