DESCKIPTION OF SPECIES. 69 



This plant, which must have been a very large and handsome one, was 

 unfortunately found only in a very fragmentary condition, only two speci- 

 mens being obtained. The best one is that given in Fig. 4. The leaflets 

 of only one side of the leaf are shown, and they are all broken and crushed 

 back, as shown in Fig. 4. The mode of insertion of the bases of these, 

 and the other specimen obtained, show that the normal position of the 

 leaflets is that given in Fig. 5. This plant has the oblique insertion of the 

 leaflets found in Ctenophyllum, but has the leaflets truncate, like the true 

 Pterophylla. Another anomalous feature is the shape of the leaflets, which 

 have their greatest width at their extremities, but maintain this width for 

 nearly half the length of the leaflet, and then narrow gradually to the base. 

 The leaflets of only one side are to be seen, and only a part of the width 

 of the midrib. As the impressions occur on a rather coarse sandstone, 

 and the nerves are very delicate and immersed in the thick leaf substance, 

 they are not fully disclosed, but appear to be as given in the diagnosis. 

 It is noteworthy that the plants found in this sandstone occur in no other 

 rock at Clover Hill, and they are very rare there. They are, along with 

 the fossil now in question, Lonehopteris Virginiensis, Clathropteris platyphylla, 

 var., expansa, Podozomites Emmonsi, Macrotaniopteris crassinervis,- &c. 



Ctenophyllum truncatum resembles closely no other previously described 

 plant, unless it be the Pterozamites spatulatus of Emmons, "Am. Geol.," 

 fig. 88. It has an obvious likeness to this plant, but in Emmons's plant 

 the leaflets are represented as rounded off in an elliptical manner at the 

 ends. Our plant is, besides, much larger than that of Emmons, both in 

 the leaflets and midrib. It may not be a true Ctenophyllum, but perhaps is 

 the type of a new genus. I do not feel at liberty to found a new genus 

 on such an imperfect fragment, but place it provisionally in the genus 

 Ctenophyllum, the one nearest to it among existing genera. 



Formation and locality. — Found only at Clover Hill in siliceous sand- 

 stone, between the lower and main coal seams. 



Ctenophyllum Brauuianum var. a, Goepp. 



Plate XXXIV, Figs. 2-4; Plate XXXV, Fig. 1; Plate XXXVII, Figs. 1, 2; Plate XXXVIII, Figs. 1, 2. 



Leaf 40 centimeters and more in length, elliptical in outline. Petiole 20 centi- 

 meters and more in length, 1 centimeter in width. It is bare of leaflets. Midrib 1 



