DESCRIPTIOJSr OF SPECIES. PP. 57 



remote ; rachis of the primary pinna, large and very rigid, 

 that of the secondary, rather slender; pinnules of the 

 lowest portion of the frond, undulate on the margin as 

 if about to become lobed, those of the middle and up- 

 per portions very entire, all oblong, obtuse, and very rigid 

 with a dense leather-like leaf -substance, slightly cut away 

 at the base on the upper side, inserted at an acute angle on 

 the secondary rachis, alternate ; mid-nerve, strong at the 

 lower portion, but splitting up and vanishing toward the 

 end ; lateral nerves in the lowest pinnules, grouped fla- 

 bellately in the lobes or forking with parallel branches, and 

 the two adjoining nerves inserted at a common point, those 

 of the pinnules higher on the frond forking near the inser-' 

 tion and sending parallel branches to the margin ; fructifi- 

 cation consisting of two rows of sori, one on eacli side of 

 the mid-nerve, elliptical in form, and leaving very sharply 

 defined i)its on the surface of the pinnules ; fertile pinnules 

 thick and dense, with no lateral nerves, and an obscurely 

 defined mid-nerve.) 



The form, and sharp definition of the impressions of the 

 sori, Avith the nervation and shape of the sterile pinnules, 

 cause our plant to resemble Heer's Asterocarpus ( Pecoj)- 

 teris) Meriani, PI. XXIV, Figs. 4, 5, 6, "Die Pfl. d. Trias 

 u. des Jura," but in our species the pinnules are separate 

 to the base. 



The fertile form given in PL XII, Pig. 2, we attribute to 

 C. oblongifolium ; though we have never seen it attached to 

 the sterile portion of the plant, we find it with the sterile 

 portions of the plant, and the resemblance in facies is evi- 

 dent. We find the fructified part of the plant, with the 

 leaf-substance preserved on the stone. This seems to have 

 been thick and leather-like, for the organic matter now re- 

 maining presents the form of a dense shining film, in which 

 we find the elliptical pits showing the places of the sori. 

 These pits are beautifully distributed, and seem to indicate 

 that the sori were placed in indentations on the surface of 

 the lamina. As the sori themselves seem to have fallen 

 out before the entombment of the plant we could not de- 

 tect their nature. 



