6 THE LATER EXTINCT FLORAS OF NORTH AMERICA. 



be always absent, and this fact gives probability to the suggestion of Mr. 

 Gardner that the fruit was borne upon independent fronds or stipes. 



Mr. Gardner suggests that Asplenium Foersteri Deb. and Ett., described 

 in the Urweltlichen Acrobryen des Kreidegebirges von Aachen und Maes- 

 tri cht, PI. II, figs. 4, 7, 11, is also closely related to if not identical with 

 Anemia siibcretacea ; but in a recent visit to Aachen I had an opportunity of 

 examining some of Debey's original specimens, and it seemed to me they 

 were very distinct from A. siibcretacea. A. Foersteri is a thinner, more 

 delicate fern, with few and slender nerves and with pinnae irregularly lobed 

 or undulate. I have identified this species among the plants from the 

 Amboy clays,, many of which also occur at Aachen. The Amboy clays 

 are about on the horizon of the Dakota sandstones, and therefore very 

 much older than the Laramie group. 



Formation and locality: Cretaceous (Laramie group). Orcas Island, 

 Bellingham Bay, Washington; Point of Rocks, Wyoming; Erie, Colorado. 



ACROSTICHUM HESPERIUM Newb. 

 PL LXI, figs. 2-5. 

 Proc. IT. S. Nat. Mus., Vol. V (March 21, 1883), p. 503. 



"Frond large, pinnate; pinnse linear, 1£ to 2 inches wide, 6 to 12 

 inches long, rounded at remote extremity, those in lower part of frond 

 rounded or wedge-shaped at base, those above united by the entire base to 

 the rachis and with each other; rachis of frond and midrib of pinnse strong, 

 smooth, somewhat sinuous; nervation reticulated, lateral nerves numerous, 

 diverging from the midrib at an acute angle, anastomosing to form elon- 

 gated six-angled areoles; fructification unknown." 



This is a large and strong fern, represented in the collections by a num- 

 ber of specimens collected by Mr. C. A. White, which include portions from 

 the lower and upper parts of the frond. In general aspect it much resem- 

 bles Acrosticlium aureum of Florida and the West Indies; but in that species 

 the pinnae are all separate and narrowed at the base, whereas in this plant 

 near the summit of the frond they coalesce, forming a broadly palmated 

 portion. Lesquereux, in his Tertiary Flora, p. 58, PI. IV, fig. 2, describes 

 a large fern with a somewhat reticulated nervation which he calls Gymno- 

 gramma Gardneri. The pinnae must have been about as large and of 

 similar form to those of the fern under consideration, and the nervation 



