4 PROCEEDINGS OF THE NATIONAL. MUSEUM vol.82 



ton. The pinnules are not elongated as in Knowlton's specimens, but 

 the venation and marginal dentition are similar. 

 Plesiotype.—V.S.^M. No. 39137. 



CLADOPHLEBIS READI, new species 



Plate 1, Figure 2 



This was probably a tree fern, if stoutness of the rachis is any 

 indication of the size and habit of these ancient ferns. The rachis 

 is 3.5 mm in diameter and bears narrow, elongated pinnae at intervals 

 of 1.3 cm. The pinnae average 10 cm in lengih and bear numerous 

 closely spaced, falcate, minutely stalked or sessile pinnules. The 

 margin of the pinnules appears for the most part to be entire, but in 

 some cases is noticeably crenulate. From the midrib of the pinnules 

 emerge 8 to 10 pairs of secondary veins, which fork once close to the 

 midrib. No sori are present on any of the specimens in this 

 collection. 



Many species of Cladophlehis have been described from Cretaceous 

 rocks. The species which this most resembles is Cladophlehis distans 

 Fontaine ^ from the Potomac group of Virginia and Maryland. The 

 chief difference between the two seems to be that most of the pinnules 

 of C. readi are conspicuously rounded at the base and are attached 

 by a minute stalk. G. readi will no doubt be compared with Dryop- 

 tens coloradensis Knowlton.'' That species, however, has more 

 widely spaced pinnae ; the venation of the pinnules is more open and 

 oblique; and the rachis is much slenderer, suggesting a different 

 habit. I name this species for my colleague, C. B. Read. 



Holofype.—\J.S.'\!^M. No. 39138. 



MICROTAENIA PAUCIFOLIA (Hall) Knowlton 



Plate 1, Figxire 4 



Microtaenia paucifolia (Hall) Knowlton, U. S. Geol. Surv. Prof. Paper 

 108, p. 82, pi. 30, figs. 1. 2, 1917. 



The specimen figured is fragmentary, but sufficient is present to 

 identify it with those described by Knowlton. 

 Plesiotype.—V.^.'^M. No. 39139. 



SPARGANIACEAE 



SPARGANIUM ASPENSIS, new species 



Plate 2, Figure 2 



This specimen has the general appearance of a Sparganium spike 

 of staminate flowers. The portion preserved is 9 cm long and shows 



s Fontaine, W. M., The Potomac or younger Mesozoic flora. U. S. Geol. Surv. Mon. 15, 

 p. 77, pi. 13, flgs. 4, 5, 1890. 



" Knowlton, F. H., A fossil flora from the Frontier formation of southwestern Wyoming. 

 U. S. Geol. Surv. Prof. Paper 108, p. 83, pi. 30, figs. 3, 4, 1917. 



