Maryland Geological Survey 451 



Described originally from the Kome beds (Barremian) of Greenland 

 by Professor Heer this author soon afterward recorded it from the 

 Upper Cretaceous Atane beds of that country. It has been recorded 

 by Nathorst from the Neocomian of Mexico and it is present in the 

 Kootanie formation of Montana. It is a member of the Shasta flora 

 of the Pacific coast (Horsetown beds) and is probably represented in 

 the Fuson formation of eastern Wyoming by what Prof. Fontaine calls 

 Sequoia gracilis. In the Upper Cretaceous, remains in every way identical 

 with these Lower Cretaceous occurrences are present in the Magothy 

 formation at Gay Head and at a number of localities in Maryland as 

 well as in the Tuscaloosa formation of Alabama. 



In the Potomac Group this species ranges from the base of the Patux- 

 ent, through the Arundel to the top of the Patapsco in considerable 

 abundance. Seward (Wealden Fl. pt. ii, 1895, p. 206) comments on 

 the resemblance between Sequoia ambiguxi Heer and the widespread 

 remains of Sphenolepis Sternbergiana (Bunker) Schenk, a resemblance 

 strikingly shown in some Wealden specimens of the latter from Eccles- 

 bourne recently received by the writer. However, their preservation 

 is not of the best and the English specimens seem to show slight differ- 

 ences from the type of this species in the direction of what in America 

 is identified as Sequoia ambigua. ISTo changes in nomenclature are pro- 

 posed, however, since it seems probable that Sphenolepis Sternbergiana 

 in. Il^orth America is properly identified and distinct from Sequoia 

 ambigua, which is more open and stouter and which may be present in 

 the English Wealden in some at least of the coniferous twigs identified 

 as Sphenolepis Sternbergiana. 



Occurrence. — Patuxent Foriiation, Fredericksburg, Dutch Gap, 

 Cockpit Point, Potomac Eun, Telegraph Station (Lorton), Virginia. 

 Arundel Formation. Soper Hall, Eiverdale, Arlington, Muirkirk, 

 Schoolhouse Hill (Hanover), Maryland. Patapsco Formation. Federal 

 Hill (Baltimore), Locust (Poplar) Point, Fort Foote, Maryland. 



Collections. — U. S. National Museum, Johns Hopkins University. 



