CORYNEPTERIS 323 



in all points with the petrified specimens of Zygopteris 

 is so exact as to make it certain that, as M. Renault 

 first suggested, they belonged to some allied species 

 of that genus. As it is also beyond doubt that 

 Schizopteris and Schizostachys belonged together, we 

 are enabled to form a fair idea of the external form 

 of both the sterile and fertile leaves of Zygopteris. 

 These fronds are included by Zeiller x in the latter 

 genus, under the name of Zygopteris pinnata. Having 

 inspected the fine specimens from Commentry in the 

 collection of the Ecole des Mines, I have no doubt that 

 the attribution to Zygopteris is correct. 



2. Other Genera. — The genus Corynepteris of Baily 

 appears, according to Zeiller's investigations, to have 

 been closely allied to Zygopteris. Several species have 

 been described, and in some the form of the frond is 

 well known. In certain of the species it is of the 

 Sphenopteris type, resembling the frond of Zygopteris 

 pinnata, but Pecopteroid fronds have also been found 

 with a similar fructification. The sori are borne on 

 pinnules, either like those of the sterile frond or com- 

 paratively little modified. The sporangia, so far as the 

 annulus is concerned, are much like those of Zygopteris, 

 but in most cases they are grouped in a ring round a 

 centre, so as to resemble the synangium of an Asterotheca. 

 Corynepteris thus, to a certain extent, combines the char- 

 acters of Marattiaceae with those of Botryopterideae. 2 



1 Zeiller and Renault, Flore fossile de Commentry, p. 76, Plate xxxii. 

 Figs. 5-7, St. £tienne, 1888. 



2 For an account of the genus Corynepteris, see W. H. Baily, Journal 

 Geol. Soc. Dublin, vol. viii. i860; Zeiller, Flore fossile du Bassin houiller 

 de Valenciennes, 1888, pp. 41 and 117. 



