DESCRIPTION OF SPECIES— FILICES. 55 



described from Golden. As it represents only the end of a pinna, the lobes 

 are of course shorter and more obtuse ; the subdivision of the secondary 

 veins is less multiplied, forming a single row of basilar areas and the veins 

 generally merely forking. This difference in that nervation is also probably 

 due to the position of the fragment relatively to the frond. This form is 

 related to Woodicardites arcticus, Heer, Flor. Arct., ii, p. 462, pi. xl, tig. 6. 



Habitat. — Black Butte, Wyoming. Days of researches at the same 

 locality failed to procure any other specimen than the fragment figured. 



Diplaziuni ITIiiellcri! Heer. 



Plate IV, Figs. 10, 10 a. 



Diplazium Muelleri, Heer, Bornst. Flor., p. 8, plate i, fig. 2 — Lceqx., Annual Report, 1873, p. 393. 



Pinnae coriaceous, simple, narrowly lanceolate, gradually tapering to a long acumen ; borders 

 margined, distantly, equally, sharply serrate; middle nerve broad, grooved ; veins at an acute angle of 

 divergence, very close, dichotomcus, and a.iastomosing in right angle by cross-veinlets. 



This Fern, as represented by the only fragment figured, is remarkable by 

 its thick substance, truly coriaceous, and its inflated, cartilaginous, sharply 

 serrate margin. By the form of the pinna and its dentate borders, it is 

 evidently related to Heer's species. It is, however, different by the nerva- 

 tion, the veins being more divided and distinctly anastomosing. As the 

 coriaceous texture of this leaf does not allow to see clearly the disposition of 

 the lateral veins, and especially the anastomoses, which are visible only in some 

 parts where the epidermis is destroyed, it might be supposed that the Euro- 

 pean specimens, in a better state of preservation, did not expose all the 

 details of nervation as they are seen upon the fragment, fig. 10 o, a part of 

 fig. 10, where the epidermis is erased. Heer mentions the leathery texture 

 and peculiar dentate borders, which in his leaf are doubly dentate, and there- 

 fore less regular than in this fragment. Though it may be of the relation 

 of these forms, the nervation with its anastomoses seems to remove the 

 American species from the genus Diplazium. It has some analogy with 

 species oi Acrostichum, A. alismc^folium, for the thick border, and A. aureum, 

 for the close anastomosing veins; but this is a distant relation indeed. It 

 might be compared also to some species of Aneimia. 



Habitat. — Henry's Fork (Dr. F. V. Hayden). 



