146 EXPLORING EXPEDITION FROM SANTA FE 



gives the impression of a large and strong plant, much more like some species from 

 the Coal-formation than any hitherto found in the Triassic or Jurassic rocks. The 

 detachment of the upper half of the base of the pinnules from the rachis is a feature 

 so peculiar that it will serve to distinguish it at a glance. At firsl sight, tins would 

 seem to be accidental; but each of the pinnules of the larger specimens contained in 

 the collection before as shows it to exist in precisely the same degree 3 so that we must 



conclude it tO be a constant character. 



This species is named in honor of Prof. J. D. Whitney, to whom I am indebted 

 for the opportunity of examining the Triassic plants collected by Mr, Remond. 



Formation and locality — Triassic strata ; Los Bronces, Sonora (Mr. Remond). 



Camptopteris Remondi, Newb. - 



Plato VII, figs. 2, 2". 



Frond digitO-pinnate or spirally discoid, -from one to two feet in diameter, con- 

 sisting of twenty or more pinnae radiating from a common center, and extended in the 

 same plane. The longest pinnae are one foot in length and one and one-half to two 

 inches wide in their central and broadest portions. By the lower fourth of their length 

 they are united; above they are free, lanceolate in outline, with margins obtusely 

 dentate or crenate. The central nerve of each pinna is strong and flat From this 

 the secondary nerves spring at a subacute angle, curve gently upward at their extrem- 

 ities, and terminate in the crenations of the border. The tertiary nervation is very 

 delicate, filling all the spaces between the secondary nerves with a somewhat irregu- 

 lar polygonal reticulation. 



This remarkable fern evidently belongs to the same genus with that figured by 

 Schimper in his Paldontologie Vegetde (plate xlii, tig 4) under the name of Camp, 

 topteris serrata, and it seems to me highly probable to the same genus as (loeppert's 

 Thtuimatoptvris Minister}. It is specifically, however, quite distinct from both of these; 

 the fronds being larger, the pinna- broader and united by a greater portion of their 

 length, and the dentition of the margins being shallower and more rounded. The 

 nervation of Camptopteris serrata is not given, but in our plant it is very distinctly 

 shown. It consists of a series of secondary nerves springing from the midrib at an 

 angle little less than a right angle. These are gently arched upward, and terminate 

 in the denticles of the border. The interval between them is filled with a polygonal 

 network of rounded or quadrangular meshes, inside of which is a finer network, hav- 

 ing the same general character, the meshes being four-, live-, or six-angled. This is 

 also the nervation of Tkaumatopteris, and since one plant, as shown by its peculiar form 

 of frond, is generieally identical with the typical species of Camptopteris, and its ner- 

 vation can hardly be distinguished from that of TTiaumatopteris, it tends to link these 

 two genera together. I should also mention that on one of the specimens brought by 

 Mr. Remond from Sonora besides the expanded pinnae of Camptopteris, we have one 

 spirally folded precisely like that figured by Qoeppert (Gattnngen, plate 1, iig. 3). 



The discovery of tins plant in the coal-strata of Los Bronces is a matter of no 

 little geological interest, as no species of Camptopteris had been before discovered on 

 this continent. It also adds to the strength of the evidence of the Triassic age of the 



