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Wenlock Shales derives its name from our district ; it is extensively quarried 

 at Soutterdine, and burnt for lime, possessing, like the lias limestone, in its 

 admixture of silica and iron oxide, the power of setting under water ; it is also 

 largely used for road metal, and may be recognized by its hardness, deep blue 

 colour, and veins of pink calc-spar : it has yielded many specimens of the two 

 fine trilobites figured by Murchison, Illcenus Barriensis and HomaJonotus 

 delphinoccphalus ; the quarrymen, whose hammers are the only ones heavy 

 enough to detach the fossils, have been enjoined to preserve the specimens 

 they find. The discovery of the Actinoceras baccatum, fignred in our Fossil 

 Sketches, ought to encourage our club to further explorations, for perhaps some 

 other rare tenant of Silurian seas may have left his exuviae in the elliptical 

 area of sea-bottom, afterwards to be upheaved into the Woolhope district. 

 Geologists want fmther information about these Woolhope beds, which we are 

 justified in regarding as our own peculiar domain. Perfect fossils from the Upper 

 Llandovery beds of Woolhope would be a great find ; the Vicar of Woolhope 

 has, I am told, some fragmentary casts of the characteristic Pentameri, but 

 the exposure is so slight that a prolonged search for fossils would be, I fear, of 

 little avail. 



I cannot leave this part of my subject without referring to a question of 

 paramount interest to a club whose sphere of action is limited to Palseozoic 

 rocks ; I mean the beginning of vertebrate life on the earth. You know what 

 triumjihs geologists have achieved in little more than thirty years ; mammals 

 have been brought down into the Upper Trias ; birds have descended step by 

 step through the Lower Eocene beds into the Upper Green sand, and lower 

 still into the Upper Oolite slates at Solenhofen, in Bavaria ; and the long- 

 cherished theory, that reptiles had their beginning in the Permian era, was 

 abandoned not without a struggle, when Professor Von Dechen revealed the 

 Archegosaurus in the clay iron stone of the Carboniferous beds of Saarbriick. 

 The Devonian fish have been found to have had precursors who left their 

 exuviae in the Ludlow bone-beds, and a member of our club, Mr. Lee, of Caerleon, 

 has detected a fragment of Pteraspis in the Lower Ludlow Shales of Leint- 

 wardine. The details of these successive discoveries may be found in " LyeU's 

 Elements" (chapter 27., Ed. 1865). I have noticed them here to remind you 

 that the progi-ess of our science has continually compelled palaeontologists to 

 modify one theory and abandon another at the inexorable bidding of facts, which 

 have proved too strong for preconceptions founded insecurely on breaks, uncon- 

 formability, or long unavailing search. 



But here in the Lower Ludlow Shales, Sir R. Murchison bids us " rest and 

 be thankful ;" not because we have hitherto worked hard, but because there is 

 no more work to be done. Let us hear his own words : "We may therefore fairly 

 regard the Silurian system on the whole, and certainly aU the Lower Silurian, 

 as representing a long and early period in which no bony vertebrated animals 

 had been caUed into existence" (p. 242., ed. 1867); much to the same effect wo 



