PTERIDOPHYTA. I5II 



and Lower Gondwanas, and is also found in New Zealand and 

 Australia. Palceovittaria seems peculiar to the Damuda series of 

 the Lower Gondwanas. Oleandridium has stalked leaves differing 

 somewhat in their venation from the preceding, and is considered 

 to be allied to the existing Oleandra among the Aspidiece ; it occurs 

 in the European Mesozoic and the Panchets. Angiqptertdium and 

 Marattiopsis are distinguished by a simple pinnation of the leaves ; 

 the former occurring in the Damuda series of the Gondwanas, and the 

 latter in the European Carboniferous. The genus Glossopteris (fig. 

 1376) is the only representative of the second subfamily, and is 

 distinguished by its net-like venation, retaining, however, the well- 

 marked midrib characteristic of the family. It is extremely abun- 

 dant in the Indian Gondwanas, ranging from the Talchir to the 

 Upper Jurassic Jabalpur stage, and is also met with in the Hawkes- 

 bury beds of Australia, in the upper part of the African Karoo 

 system, in the Cretaceous of Russia, and in beds of unknown age 

 in Italy. Finally, the Gangamopteridece 1 include Ferns with a net 

 venation, in which the leaves are subject to great variation in shape, 

 but may be digitate or fan-like, and devoid of midrib. There is 

 one division with simple, and another with compound venation. In 

 the former we have Gangamop fen's, ranging throughout the Lower 

 Gondwanas and also found in the Bacchus-Marsh beds of Victoria ; 

 and Befemnopteris of the Damudas ; both being probably allied to 

 the Polypodiacece. In the second group Camptopteris occurs in the 

 Keuper ; Dictyophyllum ranges from the Rhsetic of Germany to the 

 Cretaceous of Greenland ; while Clathropteris is confined to the 

 Rhaetic, and Protorhipis to the Lias. 



Fern-stems. — Omitting a few fossil Ferns of uncertain affinities, 

 brief reference must be made to a few types of large size described 

 upon the evidence of portions of the stem, but which cannot at 

 present be definitely classed. Of these Megaphyton, from the Car- 

 boniferous of Europe and the United States, is founded on trunks 

 of Tree-ferns, which bore their large leaves in a row on either side 

 of the stem, and which Sir J. W. Dawson considers very unlike any 

 existing type. Psaronius — a type common to the Old and New 

 Worlds, and mainly of Devonian age — is founded on trunks of 

 Tree-ferns marked by alternate leaf-scars, which are usually sur- 

 rounded by aerial roots like those of many existing forms. Caul- 

 opteris, which is likewise found in both Europe and North America, 

 is characterised by its vertically elongated leaf-scars. It ranges 

 from the Carboniferous to the Permian ; but at least some of the 

 forms described under the name of Ptychopteris, which extends 

 upwards to the Trias, are not generically separable. Protopteris, of 

 the Cretaceous of Europe and Greenland, is another large form, 



1 Usually termed Dicty opt er idee, but not including Didyopteris (p. 1507). 

 VOL. II. 2 R 



