FERNS— MEGALOrTERIDE.g^—OALLIPTERIDIUM. 1 21 



in the larger pinnae, obtuse in the smaller ; ultimate rachis fairly strong, 

 irregularly striate, rounded on the back, shallowl)'- canaliculate on the 

 upper surface, on which the pinnules are attached a little within the border ; 

 pinnules alternate, very open, usually close or nearly touching, or slightly 

 overlapping, but sometimes a little distant or appearing quite distant on 

 account of the reflexed margins, irregular in position, sometimes curving 

 upward, sometimes curving outward, somewhat polymorphous, oval or oval- 

 round, attached by the whole base and connate for a very short distance, 

 the sinus acute and slightly decurrent when young, or becoming oblong 

 or oblong-lanceolate, the obtusely rounded apex often directed slightly 

 upward, the base cut to the rachis and even constricted, both above and 

 below, to a narrow attachment at the base of the pinnae ; lamina thin, 

 dull, often preserved brownish, somewhat depressed over the midrib, arched 

 slightly backward, sometimes to a considerable extent, at the margin; 

 nervation generally rather distinct; midrib of moderate strength, depressed 

 above, rounded below, only slightly, if at all, decurrent, usually originating 

 at a very open angle to the rachis and passing, strong, two-thirds or more 

 of the way up the pinnule; nervils thin, jjarallel, rather close in the older 

 portions of the plant, originating at a rather open angle, forking once near 

 the base in the pinnules of moderate size, or both branches forking again in 

 the larger pinnules and arching but little in passing to the margin, which they 

 reach quite obliquely, the lower nervils springing directly from the rachis. 



The pinnules of this species, first described 'from Henry Count}^, are 

 somewhat polymorphous, those on the same pinna often showing a consid- 

 erable degree of irregularity. An illustration of this feature is seen in 

 Fig. 4, PI. XXXVIII, a photograph of the original of Professor Lesque- 

 reux's fig. 5, pi. xxvii, of the Coal Flora, now No. 3182 of the Lacoe collec- 

 tion. The lamina is dull and black, although rather thin, as is the case 

 also with No 3192 and No. 3187 of the same collection, both labeled Gallip- 

 teridium membranaceum by the author of the species, of whose private col- 

 lection they formerly were a part. So far as I have observed, the specimens 

 are perhaps no oftener preserved brown or translucent than are the frag- 

 ments, when somewhat macerated, of Pecopteris cUntoni Lx. Even P. vestita 

 and P. pseudovestita are frequently macerated so as to present a similar 

 brown and membranaceous appearance, thougli some traces of the villosity 

 are usually present. 



