FLORA OF THE KOOTANIE FORMATION. 297 



of the ordinary small pinnules of this specimen appear to be quite coarse 

 and interrupted in. length, which makes the parts visible look like the linear 

 sori of an Asplenium; otherwise their plan, and that of the nerves of the 

 basal pinnules, are the same as tliat of the normal pinnules. 



In Mr. Weed's collection from the Grafton beds a specimen of a small 

 fern resembling Acrostichites was seen and regarded as a new species. 

 No name was proposed for it in the preliminary report, but it was com- 

 pared with Dunker's Wealden species Pecopteris Geinitzii. The many 

 specimens of it occurring in Professor Ward's collection show that this is 

 CladophleMs heterophyUa. This specimen is represented in PL LXXI, 

 Fig. 25. 



Cladophlebis constricta Fontaine. 



PL LXXI, Fig. 26. 



1889. Cladophlebis constricta Font.: Potomac Flora (Monogr. U. S. Geol. Surv., 

 Vol. XV), p. 68, pi. ii, figs. 11, 11a, lib; pi. iii, fig. 2; vi, figs. 5, 5a, 6, 6a, 

 8, 8a, 9, 9a, 10, 11, 11a, lib, 12-14; pi. xxi, figs. 9, 13; pi. clxix, figs. 2, 2a. 



One imprint of a fern with its reverse was found in the Geyser beds 

 that is strikingly' like Cladophlebis constricta Font., of the Lower Potomac 

 strata of Virginia. The identification of this fern with the Potomac form 

 is made questionable solely because the amount of material is not sufficient 

 to permit positive conclusions, and not because this specimen is unlike in 

 any respect that of Cladophlebis. In fact, the imprint is exactly like the 

 form depicted in Monograph, United States Geological Survey, Vol. XV, 

 pi. ii, fig. 11 (not 12, as wrongly given in that work). The description of 

 this species given on page 68 of the same work applies equall}' well to the 

 specimen now in question. The Geyser specimen corresponds to the 

 upper pinnae of the Potomac form given in the figure quoted. The pin- 

 nules, however, are rather smaller. 



The Geyser specimen is the imprint of an ultimate pinna, probably 

 from high up on the frond, which carries several pinnules. These are 

 remotely placed, mostly with undulate margins, but with some having a 

 rounded shallow lobe on each side at the base. The pinnules are rounded 

 off and constricted at base, and in shape are ovate, sometimes elliptical and 

 even hastate. They are thick and leathery, with obtuse to subacute tips. 

 The nervation is of Cladophlebis type. The lateral nerves are quite coarse, 

 but rather vaguely defined. The upper ones are once or twice forked, the 



