FLORA OF TITF TKTNTTY FOiniATIOX. 333 



a l;u<!;(' ainoimt of oIIk-i- Lower Cretaceous, cliiefly Potomac, miscellaneous 

 matci-ial, and he I'epoHeil upon it at the time that he sent on his report 

 on the Potomac flora of Mrfiinia and ^Lu•^laIld, in XoNcinher-, l'.)()2. 

 In this report h(^ says: 



Ahoul 50 rock speciiucns oc-cunx'd in llic collection tioni Plaster BhilV. The 

 material is a fine-jirained, lumpy shale, lii;ht ash-tjray to nearly white iti color, w Inch 

 lias no cleavai;e. The shale, or i-alliei- I lie indiiralcil clay, is full of small hits of 

 vef^elahle matter, most of which are nuich commimited and not ideiitiliahle. The 

 only fossil that can he certainly identilied is Frenclop.sis niridiis Funl.. a ])lant. charac- 

 teristic of the (lien Rose heds of the Trinitj- grou{) in Texas. This plant here shows 

 only the iniernodesof the twigs, rarely moi-c than the leuii:ih of one internode heing 

 found in any t)ne hit. The twigs seem to have heen broken at the joints. Hundreds 

 of these fragments are emhetided in the clay. The firm, durable epidermis seems 

 to have |)reserved very well the fragments, some of which are very distinct, showing 

 the rows of minute tid)ercles on the surface, and the peculiar teeth-like leaves at 

 the nodes. There is no doubt whatever that the twigs are jointed. A few bits in 

 the clay suggest the presence of Pagiophi/lhim duhium Font., another character- 

 istic |)liint of the Glen Rose beds. The fragments are, however, too obscure to be 

 positively determined. 



We next proceeded to the typical localities in western Texas, arriving 

 at Glenrose, in Somervell County, on October 9. We had secured an 

 outfit the previous day at Granbury, Hood County, and were thus enabled 

 to study the formations passed over in traveling south to Glenrose. 

 After passing Comanche Peak we entered the Paluxy sands, in which 

 quantities of silicified wood occur. A citizen of Glenrose, Mr. .1. W. 

 Harvey, formerly of Cincinnati, where he had made collections from the 

 Cincinnati group, had l)een active in collecting the shells of the country 

 and had made a museum of his house. Besides the rich local fauna, he 

 hatl a f(>w vegetal)le impressions that interested me much. The locality 

 at which they were ol)tained was on the Paluxy River 2 miles above 

 Glem-ose, and on the following day Mr. Harvey guided the party to the 

 place and the day was spent in collecting the plants and associated 

 animal remains. The bed lies in the Glen Rose limestone, and character- 

 istic marine fossils of that group occur immediately above and below 

 the plant layer. It is a white argillaceous limestone, cleaving in smooth 

 layers which are rather thick. The plants occur throughout these layers. 

 The matrix is fine grained and well adapted to preserve them, l)ut tends 

 to break across with a somewhat conchoidal fracture. It was obvious 



