Association of American Geologists and Naturalists. 143 



past years. Thus Dr. Percival in his report on Connecticut, has describ- 

 ed and mapped the mesozoic red sandstone of that state in detail, afford- 

 ing much minute local information concerning the numerous trap dykes 

 which intersect it. Prof. Mather has in like manner in his report on 

 New York shown its boundaries and structure in Rockland county. To 

 Prof. Hitchcock we are indebted for a paper printed in our Transac- 

 tions, describing five new and interesting species of ancient bird tracks 

 in the same formation in the Connecticut valley, together with several 

 obscure fossil plants, and to Mr. William C. Redfield the thanks of the 

 Association are due, for a communication made last year at Albany on 

 the fishes and bird tracks discovered by him in the same formation at 

 Pompton, New Jersey. From Prof. William B. Rogers we have learned 

 the existence of the Posidonia Keuperi in this rock in Virginia, a fact 

 almost decisive of the European affinity of the formation. He has also 

 ia a paper printed in our Transactions settled with considerable exacti- 

 tude the age of the interesting coal rocks of eastern Virginia. The 

 limits of the mesozoic red sandstone (new red) in North Carolina have 

 been described and mapped by Pi'of EUsha Mitchell of that state. 



Mr. Lyell will probably enlarge our knowledge of the foreign affini- 

 ties of the Cretaceous strata of New Jersey, the Carolinas and Georgia, 

 by a comparison of the fossils procured by him in this countiy with those 

 of the cretaceous groups of Europe. Dr. Morton to whose patient and 

 skillful investigation of the cretaceous fossils of this country we are 

 indebted for the chief part of our facts respecting this interesting di- 

 vision of our Palaeontology, has recently laid us under new obliga- 

 tions, by figuring some striking forms, collected by the lamented Nicol- 

 let in the remote and vast cretaceous region of the Missouri. At the 

 last meeting of the Association Mr. Nicollet himself, read an interesting 

 sketch of the cretaceous beds, examined by him on the Missouri river. 



Our acquaintance with the cainozoic or tertiary strata of the United 

 States has also been materially advanced in the interval under consider- 

 ation. Mr. Conrad in a communication to the National Institute, made 

 in 1841, has presented a clear and interesting synopsis of his researches 

 among the tertiary beds of some parts of Maryland, and of the southern 

 states, and Mr. Lyell in two papers to the Geological Society, has con- 

 tributed various useful facts concerning the same strata in the Carolinas 

 and Georgia and in Martha's Vineyard. Mr. Hodge has also given the 

 Association his observations on some parts of the southern tertiary and 

 cretaceous strata. The list of miocene fossils of Virginia, has been 

 considerably enlarged by Mr. Henry Lea of Philadelphia, in a paper 



