Maryland Geological Survey 237 



KnowUonella Maxoni is remotely suggestive of the three species of 

 Phlebotneris described by Saporta from the Albian of Portugal. It is 

 named in honor of Mr. Wm. E. Maxon, of the National Herbarium, in 

 appreciation of his helpful interest in fossil f em-remains. 



Occurrence. — Patapsco Formation. Stump Neck, near Glymont, 

 Maryland; near Widewater, Virginia. 



Collections. — Johns Hopkins University, Maryland Academy of 

 Science. 



Family CYATHEACEAE 



Genus DICKSONIOPSIS gen. nov. 



The genus Dichsoniopsis is proposed as a convenient form.-genus for 

 fern fronds which show an undoubted relationship with the modern ferns 

 of the tribe Dicksoniese, but which it is impossible to correlate positively 

 with any of the existing genera of this subfamily. The term Dicksonites 

 would be preferable but it is preoccupied, having been used by Sterzel 

 to designate certain Carboniferous and Permian fern-like remains which 

 are not even remotely related to the form under discussion. 



Probably most of the older Mesozoic species of Dichsonia, of which 

 there are a considerable number, should be referred to the present genus, 

 however, only the single Potomac species is discussed in the present 

 connection. 



DiCKSONiopsis VERNONENSis (Ward) 

 Plate XXYIII, Figs. 3, 4 



Scleropteris vernonensis "Ward, 1895, 15th Ann. Rept. U. S. Geol. Surv., p. 



349, pi. ii, figs. 1-3. 

 Dryopteris virginica Fontaine, 1906, in Ward, Mon. U. S. Geol. Surv., vol. 



xlviii, 1905, p. 491 (non Fontaine, 1890). 

 Scleropteris vernonensis Fontaine, 1906, in Ward, Mon. U. S. Geol. Surv., 



vol. xlviii, 1905, p. 501, pi. cvii, fig. 10. 

 Dryopteris parvifolia Fontaine, 1906, in Ward, Mon. U. S. Geol. Surv., vol. 



xlviii, 1905, p. 541, pi. cxiv, fig. 7 (non other citations of this species). 



Description. — Frond finely divided, bipinnate or bipinnatifid. Pinnae 

 alternate, lanceolate in outline, passing distad into inequilaterally lobed 

 pinnules. Pinnules alternate, ascending; the basal pair usually about 



