350 MESOZOIC FLORAS OF UNITED STATES. 



He found a considerable number of these cycadean trunks and 

 sent some to geologists in different parts of the country. He had pho- 

 tographs made of some of the finest specimens and distributed the prints 

 far and wide, seeking to obtain the opinion of all as to their true nature. 

 The specimen sent to Sir William Dawson will be mentioned later on 

 (see p. 409)'. One seems to have found its way to South Carolina Col- 

 lege, Columbia, S. C, an account of which will also be given (see p. 411). 

 Some of the photographs have also come into my hands and will be 

 considered at the proper time (pp. 409-410), as also the fine series 

 that remained in the Marydand Academy of Sciences and were ulti- 

 mately turned over to the Johns Hopkins University, where they 

 still are. These fossils are mentioned in the first edition of Dana's 

 Geology-, 1863, page 472, as follows: "Large stumps of Cycads have 

 been found in Maryland near Baltimore; one is 12 inches in diameter 

 and 15 high. (P. T. Tyson observes that they may be Upper Jurassic)." 

 This reference is mentioned by Carruthers in his principal memoir 

 on cycadean trunks," and he states in a "postscript" to the memoir 

 that Dawson had shown him a photograph of one of Tyson's specimens, 

 and adds: 



The specimen from which it was taken was fifteen inches in height. It is obvi- 

 ously a species of Bennettites, with smaller leaf-scars than those in B. Saxhyanus. 

 Numerous axillary branches are seen, some of which are hollow in the center from 

 the fruits having perished. Doctor Dawson informs me that Mr. Tyson regards the 

 beds in which he obtained the specimens as most probabty of Wealden age. [See 

 p. 409.] 



The short paper read by Prof. E. D. Cope before the Academy of 

 Sciences of Philadelphia on June 2, 1868,* although chiefly relating to 

 the beds that I class as "Newer Potomac," evinces such a comprehensive 

 grasp of the general geological relations of the then Uttle-known Lower 

 Cretaceous brackish or fresh-water beds of the Atlantic slope that it is 

 refreshing reading even to-daj^, and I reproduce here those parts of it 

 that have a general bearing on the history of our knowledge of the Older 

 Potomac : 



These deposits belong to Meek and Hayden's Earlier Cretaceous, No. 1, which 

 contains abundant remains of leaves on the Raritan River, but no animal fossils. 



« On fossil cycadean stems from the Secondary rocks of Britain, by Wm. Carruthers: Trans. Linn. Soc, 

 Vol. XXVI, 1870, pp. 675-708, pi. liv-lxiii (see p. 679). 

 ij Proceedings, Vol. XX, 1868, pp. 1.57-158. 



