Maryland Geologicax Survey 399 



the modem genera Ahies and Dammara, largely because of their obviously 

 deciduous habit. While they are retained in the genus Araucarites they 

 are probably more nearly related to Dammara than to Araucaria, since 

 they more closely resemble both the Upper Cretaceous and the modern 

 Dammara cone-scales, and we know that the Upper Cretaceous species of 

 Araucaria already had cone-scales very like those of the modern members 

 of that genus and quite different from the scales under discussion/ 



The present species is confined to the Patapsco formation and is 

 apparently a type fossil for this horizon. 



The Lakota formation of the Black Hills region has furnished two 

 species of cone-scales, Araucarites ivyomingensis Fontaine and Arauca- 

 rites cuneatus Ward, both of which are smaller and thicker than the 

 present species. 



Occurrence. — Patapsco Formation. Ft. Foote (common), Prince 

 George's County, Maryland ; near Brooke, E. F. & P. cut at Aquia Creek, 

 near Widewater, Mt. Vernon, Chinkapin Hollow ( ?), Virginia. 



Collection. — U. S. National Museum. 



Araucarites patapscoensis sp. no v. 



Plate LXXVII, Figs. 5, 5a 



■ Description. — Deciduous cone-scales broadly rhomboidal in outline, 

 rounded above and with nearly straight lateral margins below. As pre- 

 served, 2.6 cm. in length by 3.3 cm. in greatest width, which is about 

 midway between the apex and the base, 6 mm. in width at the base. 

 The single incomplete specimen upon which this description is based 

 shows the under (dorsal) surface of a rather large scale which at first 

 sight appears to have subtended three or four seeds. A careful com- 

 parison with the cone-scales of the existing species of the genus Araucaria 

 leads to the conclusion that the organization of this Lower Cretaceous 

 cone-scale was essentially like that which obtains in the modern species 

 of Araucaria, among which the most similar are the cone-scales of 

 Araucaria Bidwilli Hooker, a native of Australia. The cone-scales were 



^ See Berry, Bull. Torrey Club, vol. xxxv, 1908, p. 258, pi. xvi. 

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