ANNIVERSARY ADDRESS OF THE PRESIDENT. 



3 5 



Lower and Upper Tremadoc. 



Prior to tlie year 1865 little or nothing was known of the Tre- 

 madoc rocks in the promontory of St. David's ; but in North Wales 

 they had been well studied by Sedgwick in 1847, and by Salter in 

 1857 ; and in 1866 Salter and Hicks catalogued all the species 

 known up to that time*. Doubtless the Lower Tremadoc series 

 are a continuation and natural close of the Upper Lingula-flags or 

 Ffestiniog series (the Middle Cambrian of Sedgwick). The strict 

 agreement, however, between the North- and South- Wales Tremadoc 

 faunas was not thoroughly understood until Dr. Hicks in 1873 care- 

 fully described and correlated the palseontological relations that 

 exist between the typical North- and South- Welsh areas. The 

 researches of Dr. Hicks into the Tremadoc fauna of the mainland 

 of St. David's and that of Eamsey Island made us then familiar 

 with the physical relation and paleeontological connexion between 

 the two areas f . The prior and incomplete observations of Hicks 

 and Salter in 1866 at Eamsey Island relative to the presence 

 there of the Tremadoc rocks, Dr. Hicks in 1872 fully confirmed, 

 being able to show their succession to, and conformable position 

 with, the hard siliceous flaggy Lingula-flags. In this research he 

 was assisted by three able and competent observers, Messrs. Hom- 

 fray, Lightbody, and Hopkinson, the last-named naturalist sub- 

 sequently contributing largely to the Arenig Hydrozoa from the 

 same area. Dr. Hicks's labours further resulted in Mr. Davidson's 

 learned paper upon the earliest British Brachiopoda, which con- 

 tains a valuable table showing the distribution of all the known 

 species of that class in these oldest British rocks (Harlech to Tre- 

 madoc J). 



Since the labours of Dr. Hicks in Wales, another important ad- 

 dition has been made to our knowledge of the distribution and 

 fauna of the Lower Tremadoc rocks of the Wrekin area, through the 

 careful research of C. Callaway, Esq., F.G.S. Mr. Callaway cor- 

 rected errors made by the Survey, Sir B. Murchison, and Mr. Salter 

 in the reading of the Harnage and Shineton beds in Shropshire. He 

 described the Lower Palaeozoic rocks that range from Wellington 

 to Kenley (CLE. to S.W.). He paid no critical attention to rocks 

 newer than the Caradoc ; but he greatly changed the previous views 

 as to the reading and structure of the county §. Mr. Callaway 

 clearly showed that the Shineton Shales are of Lower-Tremadoc 

 age, and that the " quartzite " rock that lies between the Shine- 

 ton Shale and the Wrekin represents the Hollybush Sandstone of 

 Malvern, which there underlies the black shales with Oleni, the 

 equivalents of the Upper Lingula-flags. The determination by 

 Mr. Callaway of the presence of a Tremadoc fauna in England is of 

 high importance ; and, singularly, most of the Shineton Tremadoc 



* British Association Eeport, 1866. 

 t Quart. Journ. Geol. Soc. vol. xxix. p. 39 (1873). 

 \ Geol. Mag. vol. v. (1868) pp. 303-315. 

 § Callaway. Quart. Journ. Geol. Soc. vol. xxxiii. pp. 652-672. 

 vol. xxxvii. t h 



