ilOORE ABXORilAL SECOXDAEY DEPOSITS. 493 



within which the organic remains were probably living, contempo- 

 raneously with the deposition of Liassic beds at other points. The de- 

 licacy and perfect condition of the fossils show that their presence 

 is not due to the denudation and the redisposition of previously ex- 

 isting beds within the fissures. 



We may deem it a most interesting fact, and one most difficult to 

 account for by those who still advocate the Plutonic origin of mineral 

 veins, that from this one locality there have been obtained at least 115 

 species of fossils below the Mendip horizon for workable minerals. 



A few of these in the vein above, and also in the clay at the base, 

 are, as might be expected, derived from the Carboniferous Limestone ; 

 but these species are readily distinguished from those of Liassic age, 

 and are not more than twenty in number ; they consist chiefly of 

 different species of Bryozoa and Corals, with three species of Brachio- 

 poda, viz. Terehratula liastata, Orthis Miclielini, and Atrypa. 



I found, therefore, under these peculiar circumstances, about 

 ninety-five species of Lower Liassic organisms — a larger fauna than 

 had to this time been obtained from any stratified bed of that age, 

 or, I might almost say, from the whole Liassic formation in this 

 county. Although the veins are chiefly productive in their upper 

 portions, the blue clay in which these remains are found is mineral- 

 ized, and contains almost 7 per cent, of galena. The wood in it is 

 converted into jet, and its cells filled occasionally with that mineral. 



On perusing the following list, and comparing its general fauna, 

 it will be seen that many of the species are identical with those fr-om 

 Brocastle in South Wales ; and these, again, with others from the 

 Sutton Stone, to be hereafter noticed ; whilst both those localities 

 will be found to have species in common to the so-called Infralias 

 of the Cote d'Or, Yalogne, Luxembourg, and Hettange. 



By an accident, several species of Foraminifera, in addition to the 

 twelve given in the list, were lost. Theae are intimately con- 

 nected with those from the Foraminifera-zonset the top of the Lower 

 Lias at Camerton. Eleven species of Entomostraca are included in 

 the list; and for their examination I am indebted to my friend 

 Professor Jones, F.G.S., who, however, assures me that the known 

 forms belong to species occurring in the Carboniferous rocks, some 

 having been found also in the Permian ; and that the new species 

 have their allies in the same deposits. The Brachiopoda are of 

 nine genera, several of them being specifically identical with forms 

 from the Upper Lias and Inferior Oolite. Leaving out the minute 

 Gasteropoda, which appear to unite this deposit with the conti- 

 nental beds, the general facies of the former would connect it with 

 the upper portion of the Lower Lias ; and the presence of Belemnites 

 acutus, which hitherto has not been found lower than the upper 

 part of the Ammonites- BiccHandi beds, would strengthen this con- 

 clusion. Several small casts of Ammonites were found with them, but 

 cannot be recognized specifically. 



7. Terrestrial and Freshivater Fauna. — Both palfeontologically and 

 as bearing upon my view of the former physical condition of the Men- 

 dip Hills, the recognition for the first time of a terrestrial fauna will 



