INTRODUCTION. 5 



account of tliem will be given in the jjroper place, iuul tliey will he noted 

 as belonging to Meek's collection of Baltimore plants. So far as I know 

 the only mention made hitherto of these fossils is an incidental reference 

 made by Dr. Newberry in his article on the Chinese Mesozoic plants col- 

 lected by Pumpelly.^ 



Mr. P. Tyson, while State geologist of Maryland, obtained in 1850 

 two cycad trunks. They were found in the above-mentioned clays extend- 

 ing from Washington to Baltimore. One of them was found near Contee's 

 Station, a point on the Baltimore and Ohio Railroad two miles southwest of 

 the town of Laurel, and the other near Beltsville, a station on the same 

 railroad a few miles nearer Washington. These trunks, now in the Museum 

 of the Maryland Academy of Sciences at Baltimore, are described in this 

 menwir. I think no previous description has been published. They were 

 photographed by Mr. Tyson, and copies of the photographs were furnished 

 by him to a number of his correspondents. Various writers have made 

 reference from time to time to these trunks. ]\Ir. Tyson, Professor Rogers, 

 and Prof P. R. Uhler, of Baltimore, have regarded them as indicating the 

 Wealden age of the clays which afforded them. Professor Uhler first 

 found the plant locality at Fredericksburg from which I collected, lie 

 says that when he discovered the spot he collected several boxes of 

 specimens and sent them to Prof. Louis Agassiz, at the Museum of Com- 

 parative Zoology, Cambridge, Mass. According to , Pi'ofessor Uhler these 

 impressions were finer than any found since at this place. I can well 

 believe this, for I have observed in collecting at the Fredericksburg locality 

 that the plant-impressions became poorer and fewer as the stratum was 

 followed in from the outcrop. I have not been able to learn what became 

 of these specimens. 



Professor Uhler placed a number of the plants collected here in the Mu- 

 seum of the Maryland Academy of Sciences, where they were subsequently 

 seen by me. They were the first that I ever saw coming from the Potomac 

 formation. Professor Uhler found at Baltimore also a number of plant- 

 impressions. They came mainly from Federal Hill. Unfortunately both 

 these and his Fredericksburg- collections have been lost. Owinof to a mis- 



' Smithsonian Contributious to Kuowledgo, vol. XV, No. 202, 1867. pp. 119-123, PI. IX. 



