284 Systematic Paleontology 



species of Asplenium, notably Asplenium Dicksonianum Heer/ suggest 

 themselves for comparison. While the writer has not ventured to include 

 any of them in the synonymy of this species, they certainly are very 

 close to this type in appearance. The English forms are questioned in 

 the synonymy, since Prof. Seward ^ considers the Wealden material iden- 

 tical with that of Onychiopsis psilotoides. This may be true of the 

 English material, but it cannot apply to that from America and Asia, 

 as the writer has shown under the discussion of Onychiopsis psilotoides. 



Occurrence. — Patuxent Eoemation. Fredericksburg, Trents Eeach, 

 Cockpit Point, Dutch Gap, near Potomac Pun, Colchester Road (Pohick 

 Creek ?), Virginia; New Eeservoir, Ivy City, District of Columbia. 

 Arundel Formation. Langdon, District of Columbia; Arlington, Mary- 

 land. Patapsco Formation. Federal Hill (Baltimore), Ft. Foote, 

 Overlook Inn, Vinegar Hill, Maryland; near Brooke, White House Bluff, 

 Mt. Vernon, Chinkapin Hollow, Virginia. 



Collections. — U. S. ISTational Museum, Goucher College. 



Family HYDROPTERACEAE 



Genus SAGENOPTERIS Presl 

 [In Sternberg, Fl. Vorwelt, Bd. ii, 1838, p. 164] 



This genus was founded by Presl in 1838 upon material from the 

 Ehsetic beds of Strahlendorf, near Bamberg, which he named Sagenop- 

 teris rhoifolia, although admitting that it was identical with that de- 

 scribed two years earlier by Sternberg as AcrostichHes incequilateralis. 

 As it is now generally admitted that the Filicites Nilsoniana of Bron- 

 gniart, described in 1825 from the Ehsetic beds of Schonen, is the same 

 species, the proper specific name of the type becomes Sagenopteris Nil- 

 soniana, as pointed out by Ward in 1906, 



Presl characterized the genus ^s follows : " Frons pinnata, pinnis 

 ternatim rarius binatim compositis. Vense tenuissimge, ramosissimse, 



^Heer, Fl. Foss. Arct., Band iii, Ab. 2, 1874, p. 31, pi. i, figs. 1-5; ibid.. Band 

 vi, Ab. 2, 1882, pp. 3, 33, pi. ii, fig. 2; pi. xxxii, figs. 1-8. 

 ^ Seward, Ann. S. Afr. Miis., vol. iv, 1903, p. 7. 



