Maryland G-eological Survey 487 



specimens. As pointed out by the writer in 1902, the Federal Hill 

 material is simply a small form of the same species. 



This late Lower Cretaceous species may be duplicated by many of the 

 leaves of the still existing species of Sassafras. It is also closely com- 

 parable with a number of other described fossil species, as for example, 

 some of the forms which have been referred to Aralia groenlandica Heer 

 in which subordinate lateral primaries are not developed and the lobes 

 are full and rounded and not straight margined (cf. Heer, Fl. Foss. 

 Arct., Band vi, Abth. ii, pi. xxxviii, fig. 3). The present species is also 

 extremely close to Sassafras arctica described by Heer^ from the Atane 

 beds of Greenland as well as to what Ward ^ identifies as Sassafras mudgH 

 from the supposed Dakota sandstone of the Black Hills region and from 

 the Cheyenne sandstone of southern Kansas. 



Occurrence. — ^Patapsco FoRMATioisr. Federal Hill (Baltimore), 

 Stump ISTeck, Maryland ; near Brooke, Virginia. 



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



Sassafras potomacensis sp. no v. 

 Plate XCIY, Fig. 1 



Description. — Leaves of relatively small size, palmately trilobate. 9 

 cm. in length by 7 cm. in width from tip to tip of the lateral lobes. 

 Sinuses mediumly open, rounded, not extending more than half way to 

 the base. Lobes narrowly conical, pointed. Base cuneate. Primaries 

 three, diverging from the extreme base of the leaf or just above it. 

 Secondaries mostly concealed, a single one can be madp ovX on the right 

 running from the midrib to the sinus in a manner quite characteristic 

 of the existing Sassafras. Texture thin but coriaceous. 



This species is based upon rather poor material from several localities 

 of Patapsco age. It is clearly different from any described species and 

 while not positively determinable as a species of Sassafras, it agrees in 

 its general facies with the various species commonly referred to this 



^ Heer, Fl. Foss. Arct, Band iii, Abth. ii, 1874, p. 109, pi. xxxi, figs. 3a, b. 

 2 Ward, 19th Ann. Rept. U. S. Geol. Surv., pt. ii, 1899, p. 705, pi. clxx, figs. 4, 

 5; pi. clxxi, fig. 1. 



