5G PP. REPORT OF PROGRESS. FONTAINE & WHITE. 



for no Callipteridium has been found in this State below 

 the Pittsburg Coal. Many of the Pecopterids of the Upper 

 Carboniferous show a tendency to assume the characters 

 of Callipteridium. 



Callipteridium Dowsonianum, Sp. nov., PI. XIII, Figs. 

 1-2, and PI. XIY, Fig. 1. 



(Frond, tripinnate, or tripinnatifid; rachisof the primary 

 pinna, strong and rough ; secondary pinnae, lanceolate- 

 linear, alternate, going off at an angle of from 45° — 60° ; 

 secondary rachis, rather strong ; pinnules, united at the 

 base, ovate and inclined slightly towards the apex of the 

 pinna, terminal pinnule, rounded-elliptical, or obovate, 

 lowest pinnule on the lower side, half inserted on the j)ri- 

 mary rachis ; mid-nerves of the pinnules, strong, and van- 

 ishing toward the apex of the pinnule ; lateral nerves, 

 forked near the insertion, and again forking near the mid- 

 dle of the lamina, arising at a very acute angle, the branches 

 curving out and passing off nearly 23arallel to each other, 

 the lowest nerves of adjacent pinnules meeting at the 

 sinus, several nerves arising from the secondary rachis be- 

 low the insertion of the mid-nerve. 



This splendid plant, which we have named in honor of 

 Principal J. W. Dawson, the distinguished paleo-botanist, 

 is very large, and must have been arborescent. We find 

 its huge fronds spreading over the surface of the shale, and 

 the fragments seen are sometimes 2 feet wide and 3 feet 

 long, as was the case with the specimen of whicli one of 

 the primary pinnae is depicted in Fig. 1, Plate XIII. The 

 texture of the pinnules seems to have been coriaceous, and 

 thick. The nervation and facies of the plant are much like 

 those of Heer^ s Meraniopteris angusta^ figured in his "Pfl. 

 d. Trias u. Jura," PL XXXVII. 



Plabitat — Roof shales of the Waynesburg Coal, West 

 Union, West Virginia. 



Callipteridium ohlongi folium, Sp. nov., PI. XII, Figs. 

 1-6. 



(Frond, tripinnate ; secondary pinnae rigid, and rather 



