SUGGESTED GENETIC RELATIONS. 125 



i 



according to Newberry, an equal degree of affinity to Alethopteris and • 

 Teeniopteris, and is separated from Teeniopteris only on account of its once 

 or twice pinnate frond and the oblique nerves. It is interesting to note, 

 in connection with this circumstance, the case of the Alethopteris macro- 

 phylla described from the same horizon by Newberry, who says that but 

 for the rectangular nervation lie should be inclined to include it in 

 Neriopteris, while Lesquereux, on the other hand, refrained from referring 

 it to Teeniopteris- only because it was pinnate, placing it in Daneeites in- 

 stead. The backward rolling of the margin of Neriopteris may be only a 

 more pronounced phase of what is common in species of Alethopteris, or 

 it may be an indication of fructification. Newberry's description and 

 figure of Neriopteris lanceolata 1 may with advantage be compared with 

 those given by Lesquereux 2 under the name Megalopterisf marginaia. 



Systematic Position and Relations of the megalopterid G roup. — A critical 

 comparative study of the alethopteroid megalopterids will hardly fail to 

 lead to the conclusion that in the early part of, perhaps before, the Sub- 

 carboniferous, the Megalopteris stock attained a high differentiation, in 

 which the Alethopteroid group produced in Neriopteris, Orthogoniopteris, 

 Alethopteris, Protohlechnum and Danseites (Heer-Schimp.) certain forms 

 embracing the essential characters of the pinnate Tseniopteridese. From 

 this Lower Carboniferous group, doubtless including many undiscovered 

 variations, may well have descended such forms as the Teeniopteris mis- 

 souriensis in the Lower Coal Measures of the American continent, the T. 

 jejunata, Grand Eury, and T. carnoti, Zeill., of the Upper Coal Measures of 

 France, or the perhaps somewhat doubtful megalopteroid, T. truncata, 

 Lesq., 3 from the Conglomerate series. 



As interpreted by superficial characters, the sequence of the Paleozoic 

 tseniopteroid types into the Triassic forms, many of which have at some 

 time rested in the genus Teeniopteris until the fruiting, either of them- 

 selves or of contemporaneous obviously generically identical species, has 

 been discovered, proving them to be true ancestors of living genera in 

 the Marattiaceee, affords strong evidence at once both of the great an- 

 tiquity of the group and its lineal descent from the Megalopteris stock. 



The figures of Goeppert's Teeniopteris munsteri, from the Rhetic of 

 Bavaria, given by Schimper* on referring the species to the genus Ma- 

 rattia, though apparently diagramatic in part, and those published by 

 Bartholin 5 deserve a comparison with Neriopteris and Dana ilex of the 

 type macrophylla, Newb. sp., and the species becomes more interesting 



1. Geol. Sunr. Ohio, Pal. I, p. 381, pi. xlv, figs. 1-3, 3a. 



2. Coal Flora, I, p. 152, pi. xxiv, tig. 4. 



3. Coal Flora, III, p. 743, pi. xciv, fig. 8. 



4. In Zittel : Traite, II, p. 85, fig. R4; Traits pal. vfig., Atlas, pi. xxxviii, fig. I. 



5. Botanisk TMsskr., vol. xviii, hft. 1, 1802, p. ■£',. pi. ix, tigs. G, 9. 



