20 FLOEA OF LOWER COAL MEASUKES OF MISSOUEI. 



meut; lamina thick, witli dull luster, covered, like the rachis, with clear, 

 sharp, irregular, fine intermittent striae, parallel in general to the nervation, 

 and apparently representing rows of closely appressed trichomes or scales; 

 nervation Pseudopecopteroid, though usually tota;lly obscured in the coria- 

 ceous lamina, the nerves originating in a single decurrent bundle and 

 forking twice or more at a moderate angle, while arching to meet the 

 borders nearly at a right angle. 



The material before me, while clearly representing a well-defined 

 species, does not exhibit the pinnation sufiiciently completely to give an 

 entirely satisfactory diagnosis of the frond. The rachis, with broad, leath- 

 ery border, a portion of which, seen from beneath, is shown in PI. IV, is 

 strikingly similar to that seen in a remarkably fine slab of Mariopteris 

 nervosa in the Lacoe collection, which aff'ords very interesting evidence of 

 a lax or possibly a prostrate habit of growth for those ferns. 



The most remarkable and constant character is the spreading, very 

 broadly cuneate, truncate lobe, dividing once or more according to an 

 unequally bilobate system, as seen in Figs. 5, 6, PL V. 



This mode of lobation is very nearly like that of Eremopteris Cheat- 

 liami Lx.,^ or Splienopteris solicla Lx.,'^ while the elongation of the rachis into 

 a blunt, spiny production in the process of pinnation is like that seen in the 

 group represented by Mariopteris (or ^^ Pseudopecojiteris") muricata. The 

 SphenopAeris solida of Lesquereux may at some future time be identified 

 with our species; for the specimen published in the Coal Flora was shown 

 so erroneouslv, without uncovering the lobes of the pinnules or dejjicting 

 the rachjal characters, that I am not wholly certain that my separation of 

 Eremopteris hilobata is reall}^ correct. The former should be re-illustrated. 



The species seems, notwithstanding its Pseudopecopteroid characters, 

 to be properly included in the genus JEreinopteris, although constituting one 

 of the several intermediate forms that, in my opinion, show the relation of 

 Psemhpecopteris to Triphyllopteris, through the Eremopteroid types. 



LocaUtij. — Specimens sent by Dr. Britts, in 1892, as a special consign- 

 ment, from Owens's coal bank; U. S. Nat. Mus., 5659, 5699, 5700, 5701, 6036. 



' Coal Flora, vol. iii, p. 769, pi. ci, tig. 3. 



- Op. cit., p. 770, pi. civ, figs. 2-4. It may, iudeed, well be asked whether all these do not belong 

 to the same genus. 



