FOSSIL PLANTS. 421 



This large and splendid fern is somewhat related to A. Serlii and some 

 other species of the same section. The essential characters which sepa- 

 rate it are, 1st, the great length of the frond, which measures at least 

 fifty centimeters ; 2d, its linear-lanceolate, or, rather, oblanceolate form, 

 the leaflets decreasing in length toward the base ; 3d, the linear, taper- 

 pointed form of the leaflets; and, 4th, the always simple division of the 

 frond. 



Fig. 1 represents the lower part, and fig. 2 the top of the frond. Fig. 

 2a shows the nervation, but the nervules are generally more nearly par- 

 allel as they approach the margin than is here represented. 



But a single specimen of this fine fern has been found. 



Locality the same as the last. 



Aletiiopteris Bunburyi (sp. nov.). 



Plate 51, figs. 3 and 3(6. 



Pinnate or bi-pinnate, with a slender rachis. Pinnae alternate, almost 

 contiguous, ovate-lanceolate or broadly oval. The margins of the upper 

 leaves sometimes entire, while those of the lower are more undulate or 

 slightly lobed. The upper leaves are attached to the rachis by the 

 whole base, while the lower ones are somewhat narrowed and very 

 slightly cordate. 



Medial nerve strong, extending nearly to the apex. Nervules gener- 

 ally once, sometimes twice dichotomous, rising from the medial nerve at 

 an acute angle and curving to almost a right angle with it, and proceed- 

 ing to the margin in lines nearly parallel. 



This pretty fern resembles very much A. tseniopteroides, Bun., found in 

 the coal fields of Cape Breton. The nervation is quite similar, but the 

 leaves are not decurrent, are more pointed, and are general-ly lobed in 

 the margin. 



Locality same as the last. 



Alethopteris maxima (sp. nov.). 



Plate 50, figs. 3, 3o, and 36. 



This species includes a few fragments of a plant remarkable for the 

 size of its pinnse, which resemble in nervation the A. tseviopteroides of 

 Bunbury. 



No basal part of a pinna has been found, and nothing is known of the 

 method of its attachment to the rachis. 



The pinna3 are oblong-linear, entire, rounded, and tapering to an acute 



