SELLARDS: NEW GENUS OF FERNS. 183 



ceous layer on the rock, petiolate, broadest in the middle, ta- 

 pering to base and apex. Rachis strong, rigid, continuing well 

 towards the apex of the frond, roughly marked with longitudi- 

 nal striiip ; in the fossil condition flat, or the original more or 

 less cylindrical shape indicated by a depression in the stone, 

 about one-third w'ider than deep, partly filled with carbona- 

 ceous matter. Petiole of the frond very strong, striate, 1 cm. 

 wide at the base, broken off short, as if detached from an arbo- 

 rescent stem or possibly a larger division of the frond. Pin- 

 nules close, connate or overlapping at the base, alternate or 

 subopposite, oblique to the main rachis, or lower ones reflexed, 

 linear ; base sessile, decurring or strongly auricled below, some- 

 w^hat rounded above, borders entire, straight, and nearly paral- 

 lel. Pinnules sloping very gradually from the base to the obtuse 

 apex, varying much in size and shape according to the position 

 on the frond ; those at the middle reaching a length of 13 cm. 

 and a width of 2 cm. at the base, strongly auricled, the auricle 

 overlapping tw^o-thirds of the distance to the midrib of the next 

 pinnule belo\v ; those at the base of the frond open or reflexed, 

 more narrow in proportion to their length, less distinctly auri- 

 cled or merely connate, or even distinct ; those towards the 

 apex also reduced, broader in proportion to their length, be- 

 coming near the apex broadly oblong, oblique, wath decurring 

 base, 1 or 2 cm. long, 1 cm. or more wide. Mid vein of the pin- 

 nule broad but shallow^ continuing two-thirds the length of the 

 pinnule, then gradually fading out. The center of the furrow is 

 marked by a narrow depression, which shows in the cast of the 

 upper side of the frond (photo pi. XL) as a fine, distinct line 

 running through the center of the pinnule. Lateral veins in- 

 distinct, thin, almost hidden in the epidermis. They leave the 

 midrib obliquely, curve outwards, and meet the borders almost 

 at right angles, simple or forked once, 12 to 14 per cm. The 

 veins of the auricles are strongly curved, often once forked. 

 Occasionally the auricle shows a very slight constriction of the 

 base of the pinnule, as if about to become lobed. 



Three good specimens of this species have been found, but 

 none of them showing the complete apex. On the same rock 

 with the basal part of the frond, fig. 1, plate XXXVIII, occurs 

 a part of a frond from near the apex, probably referable to this 

 species, with broadly oblong pinnules, close, oblique, and grad- 



