DESCRIPTION or THE SPECIES. 181 



out exartly. I'l. LXXXllI, Fh^. 5, tVoiu the Potomac Itiiu locality, indi- 

 cates that it Iiad at the l)a.se of the leaflets a stout pedicel. PI. LXXXII, 

 Fig. 2, i'rom Fredericksburg, is a fragment of what must have been a very 

 large leaf. The lower or posterior margin of this leaf is nowhere shown. 



PODO/AMITES ACUTIFOLIUS, sp. nov. 

 Plate LXXX, Fij,'. li ; Plato LXXXV, Figs. 10, 15; Plair LXXXVII. Fig. 1 ; Plato CLXX. Fig. •,'. 



Leaves very deciduous, varying in length, ()I)long, subacuminate, main- 

 taining the maximum width to near the base, and then suddenly rounded 

 off and attached by a short pedicel ; nerves branching near the base, and 

 one branch sometimes forking again higher up ; at the tips of the leaflets 

 the nerves converge to a common point, quite distinct. 



Localities: Fi.shing-hut aljove Dutch (lap Canal ; Deep Bottom ; near 

 Telegraph Station ; road-side near Potomac Run ; bank near Brooke ; rare. 



The leaves of this j)lant are much like those of Podozamites lanceolatus 

 Scliimper, and the larger leaves resemble Poilozainife.i Emmonsi Newlierry. 

 The smaller ones resemble 1\ tcnuiiicrvis. 



I take this opportunity to correct an oversight made in Contributions 

 to the Knowledge of tlie Older Mesozoic Flora of Virginia (Mon. U. S. Geol. 

 Survey, vol. 0) with reference to the employment of the name Poduzamitcs 

 Emmonsi. This name I used for a Podozamites found by Emmons in the 

 Rhivtic of North Carolina, overlooking the fact that Professor Newberry 

 had already used this name for the same plant in his article on the Chinese 

 Mesozoic plants in Smithsonian Contributions to Knowledge. 



DIOONITES Bornemann. 



Leaves ([uite large, with strong rachis ; leaflets attached on the upper 

 side of this by the whole width of the base, sometimes expanded at base so 

 as to extend up and down the rachis, linear-lanceolate or elongate-linear, 

 acute at tips, of Arm leathery consistency ; nerves simple and parallel. 



This description of Schimper given to the genus agrees exactly with 

 certain forms that are very common in the Potomac flora. Tlie plants 

 placed in the genus IJioonites are by far the most abundant cycads in tlic 



