ANNIVERSARY ADDRESS OF THE PRESIDENT. CVll 



point, I will only refer you to an able review of Murchison's * Siluria,' 

 in * Silliman's Journal*/ 



The Geological Surveys of the different States in America appear 

 to be making satisfactory progress. The Annual Report on the 

 Geological Survey of the State of Wisconsin by Dr. James Percival, 

 who commenced his labours in August 1854, has recently been pub- 

 hshed. In it the rock strata of the lead region are described ; Dr. 

 Percival appears to be incUned to the view that the lead occurs in 

 veins, instead of deposits or beds. This view has not hitherto been 

 generally admitted. 



The first Annual Report of the Geological Survey of the State of 

 New Jersey, for 1854, has also been lately published at New Bruns- 

 wick. Mr. Cook, the assistant geologist, recognizes in the cretace- 

 ous strata, three distinct beds of greensand marl, alternating with 

 strata of sand. The lower marl bed is 30 feet thick, and contains 

 Exogyra costata, Gryphcea convexa, Ostrea falcata, Terehratula 

 Say Hi Belemnites Ame7icanus, &c. The second contains Gryphcea 

 convexa and Terehratula Harlani in great numbers. In the third 

 bed fossils are rare. 



A paper on the changes which take place in the structure and 

 composition of mineral veins near the surface, with particular refer- 

 ence to the East Tennessee Copper Mines, by J. D. Whitney, is 

 published in Silliman's American Journal, vol. xx. p. 53. 



South America. — I have heard with great regret of the death of 

 Dr. Voltz, a distinguished German naturalist and geologist, who was 

 travelling in South America. He was exploring Surinam and died 

 at Paramaribo. His most interesting discovery was that of several 

 quaternary deposits at different heights above each other, containing 

 the shells of Mollusca now found living on that coast. Prof. F. Sand- 

 berger, who has seen the collections he has sent home, mentions as 

 instances of these Mollusca found at various elevations, Marginella 

 ccerulescens. Purpura cataracta, Ranella granulata^ and Venus 

 Domhyiy all of which are now found on the same coast. 



It is not improbable that they belong to the same formation as 

 that described by Col. Henneken in St. Domingo, many of the fossils 

 of which were described by INIr. Moore in a former volume of our 

 Journal. These latter, however, were referred to the tertiary period. 



Colonies of Great Britain. — From our colonies in the southern 

 hemisphere, we have, during the past year, received much valuable 

 information respecting the geological structure of those regions. 

 Natal, and other districts of Southern Africa, Australia, and New 

 Zealand have each contributed to this accession of our knowledge, 

 and I regret that the space allotted to an annual address will not 

 permit me to do more than briefly to allude to them, referring you 

 for further and more detailed information to the recent numbers of 

 our Quarterly Journal. From the district south of Natal we have 

 had a notice of some cretaceous rocks by Capt. Garden, who suc- 

 ceeded in collecting an interesting suite of fossils from the cliffs and 

 walls of caves near the river Umtafuna. These fossils have been 

 * Vol. xix. N. S. 1855, p. 373. 



