liv PROCEEDIIirGS OF THE GEOLOGICAL SOCIET'?. 



Exploring, in ascending order, from the Silurian base of the 

 Lake region, and working eastwards, the surveyors will next have 

 to develope the structure of the great mineral fields of Durham 

 and Northumberland. The vast importance of these counties, in 

 respect to their ores of lead and beds of coal, has rendered it, the 

 Director- Greneral thinks, imperative to hasten their survey, by 

 carrying on the work into them from the West and iNTorth Ridings 

 of Yorkshire before the geology of the eastern counties of England 

 is begun upon, the latter being void of all valuable minerals, save 

 Coprolites. 



In the mean time every tract south of London, and extending 

 from the metropolis inclusive to some distance directly north of 

 it, has been surveyed. 



It would be out of place here to dwell upon the good services 

 of the various surveyors, most of them Eellows of this Society, who 

 are now working out the details of geological outlines and rela- 

 tions in various parts of Great Britain, or those of Ireland under 

 the able direction of Mr. Jukes ; but I may call attention to a 

 change in, or rather addition to, the classification adopted in maps 

 already published. I allude to the interpolation of the Ehsetic 

 beds of foreign geologists as a zone lying between the Keuper 

 and the Lias. This has been carried out in certain sheets of 

 Somerset, Gloucester, &c. by the labours of Messrs. Bristow and 

 Etheridge. In searching for the best name to be used as a British 

 equivalent for the word " Ehsetic," the Director- General, after 

 personal inspection of some of the best typical localities, has 

 adopted the name of " Penarth," first suggested to him by Dr. 

 "Wright, because in the headland of that name near Cardifi", these 

 beds are most clearly exhibited, lying between red Keuper strata 

 beneath and the Lower Lias above them. 



I must also say, in reference to the Survey, that I learn with 

 pleasure that the sale of the Government Geological Maps has 

 largely increased, this being the best proof that the public are 

 taking increased interest in the advancement of our science. 



In addition to the progress of the Sxirvey itself, several memoirs 

 have also been published under its auspices, and amongst them is 

 one by Professor Huxley " On the Structure of the Belemnitid?e," 

 clearing up many points in their organization that have hitherto 

 remained more or less obscure. The specimen which has enabled 

 Professor Huxley to work out the details on which his discoveries 

 are founded is from the collection of the Eev. Mr. Montefiore, and 

 is the most complete Belemnite ever found. One of the new points 

 contained in this Memoir is the account of that rarely preserved 

 organ hitherto known as the " pen " or osselet, but to which Pro- 

 fessor Huxley has given the name oi pro-ostraciim, as he considers 

 it to correspond to only a part of the structure known as the " pen " 

 in recent Cephalopods. He then states his belief in the systematic 

 importance of the variations in form of t\ie ]pro-ostracum, and on 

 this account is disposed to favour a subdivision of the genus 

 Belemnites itself ; the difference between the fro-ostraca of certain 



