120 I). WHITE — A NEW T-SJNIOPTEROID FERN AND ITS ALLIES. 



in view of the discovery in the Conglomerate series of Ohio of a form 

 thoroughly Mesozoic in aspect that has been referred to the genus 

 Danseites (Heer-Schimp.) by Lesquereux. From the study of many 

 specimens of Tasniopteris munsteri, Goepp., fruiting from the Rhetic of 

 Bavaria, Schenk was led 1 to refer the species without hesitation to the 

 genus Angiopteris, being unable to find any character warranting a ge- 

 neric separation. Raciborski, on the other hand, is convinced that the 

 fruiting of what he considers the same species in the Rhetic of Poland is 

 that of the true Marattia. A nother tasniopteroid species which merits con- 

 sideration is the Danasopsis marantacect ( Presl.) Hcer, from the Keuper, the 

 fruiting of which is distinctly marattiaceous, and which was regarded by 

 Schenk 2 as very close to the living Dana a. The fine illustrations of this 

 species given by Schimper 3 may with great interest be compared with 

 the Megalopteroid group from Ohio. The habit of Schimper's specimen, 

 representing the upper portion of a pinna, seems such as to suggest that 

 the lower pinnules may be distinct and not confluent, a suggestion em- 

 phasized by the figures given by Schoenlein 4 and Saporta. 5 



As tending to confirm this view, I may add that in Pseudodanasopsis, a 

 genus of plants from the Upper Trias of Virginia, separated by Fontaine 

 from Danasopsis chiefly on account of its anastomosing nerves, the lower 

 and middle pinnules of the species P. reticulata, Font., represented by 

 numerous specimens in the United States National Museum (No. 3488), 

 are distinct, distant, equilaterally rounded at the base and in all re- 

 spects distinctly tseniopteroid, except for the frequent anastomosis of the 

 nervils, although the upper portions agree to a great extent with the 

 habit and characters of Danasopsis marantacea. 



The establishment of the existence of the actual genera Angiopteris or 

 Marattia in the Rhetic attributes to them a remarkable antiquity, un- 

 equaled, so far as I know, among any other living fern genera; but indis- 

 putable specimens of Dansea, with their fructification, were described by 

 Zigno 6 from the Lias of Verona, proving for this genus a nearly equal 

 antiquity. It follows that the epoch of indefinite length marking the 

 genesis or lineal descent of these two marattiaceous genera must there- 

 fore have terminated by the close of the Triassic. However, since none 

 of the forms of the Danasopsis or tseniopteroid Danasites types have been 

 found with distinct fruiting earlier than the Keuper, the direct lineage 

 of the actual genera cannot be traced backward into the Paleozoic with 

 any greater definiteness than a high degree of probability or likelihood. 



1. Die loss. Pflanzeur., p. 30, (i.e. HB. 



2. ( »p. cit.. p. 35. 



:;. Traits pal. v6g., Atlas, pi. xxxvii, figs. l-:t. 



I. A.bbild., pi. vii, lig. 2. 



5. V6g. Jurasa., I, pi. Ixv, p. 154. 



(i. PI foss. oolit., \<<\. I, pi. xxv. pp. -.'os, 209. 



