TUDOR SPECIMEN OF EOZOOlf. 349 



and but for the discovery of better material probabl}- no value would 

 have been attached to it by other writers. But as the disbelievers 

 in Eozoon were as ready then as now to admit that the production 

 of such a specimen would at once settle the whole controversy and 

 conclusivelj' establish its organic origin, the claims baaed by Sir J.W. 

 Dawson on the Tudor specimen had an enormous influence in con- 

 tirming geologists in their acceptance of the supposed Laurentian 

 fossil. The value attached to the preservation of Eozoon in a lime- 

 stone may be illustrated by the following quotation from Sir War- 

 ington Smyth's Presidential Address to the Geological Society in the 

 year of the publication of the Tudor memoir : — " The elaborate argu- 

 ments of Messrs. King and Rowney in favour of the mineral origin 

 of ' Eozoonal ' structure had at one time a strong show of support 

 in the fact that these appearances were always observed in serpen- 



tinous limestones (ophicalcites) only But the announcement 



made by Dr. Carpenter, in the Quart. Journ. Geol. Soc. for August 

 last, of Dr. Dawson's discovery of Eozoon preserved in carbonate of 

 lime pure and simple would appear to close the discussion "*. 



Sir J. W. Dawson's view apparently is that the specimen consists 

 of a slab of Eozoon 6 inches long by 4^ inches wide and 2 lines in 

 thickness, broken off at right angles to the septa. Profs. King and 

 Rowney t bubsequeutly pointed out the improbability of so large 

 and thin a slab being thus formed transverse to the laminae, and 

 suggested that the calcite veins were merely produced by infiltration 

 into a series of fissures or cracks. 



But as this opinion was only based on second-hand information 

 no great weight seems ever to have been attached to it, and from 

 that time onwards the Tudor specimen has alwa} s remained the great 

 obstacle to the acceptance of the mineralogical explanation of the 

 structure of Eozoon. Thus Prof. Moebius, after an examination 

 of the specimen, told Mr. C. D. Shcrborn and myself that it alone 

 had ever suggested to him doubts as to the truth of his conclusions, 

 l^rof. Nicholson, moreover, allows me to say that he has always 

 felt that if the Tudor specimen should exhibit the characteristic 

 canal-system of Eozoon, it would afford a strong presumption in 

 favour of the view that Eozoon is organic ; and that after an exami- 

 nation of the specimen he saw nothing that would justify the 

 assertion that its nature was organic, or even that the specimen was 

 one of Eozoon at all. 



The specimen having recently been sent to England for examina- 

 tion by a committee which had arranged to work through the 

 enormous mass of Eozoonal material collected by the late Dr. W. B. 

 Carpenter, I have had the opportunity for a careful study of it. 

 For this 1 am indebted to Dr. P. K. Carpenter, F.R.S. ; I must also 

 express my best thanks to Dr. R. A. C. Selwyn, C.M.G., for his 

 kindness in allowing a further section to be prepared, which has 

 been skilfully cut by Mr. Ryley. Dr. Selwyn has moreover allowed 



* Op. cit. Proc. p Ixiv. 



t ' On Eozoon camidcmse,' Proc. E,oy. Irish Acad. vol. x. (1870) p. oil. 



