PALEOBOTANY BERRY. 



389 



A fern-like genus, Thinnfeldia, of undetermined botanical affinity 

 that appeared in the Rhaetian or uppermost Triassic in Australia, 

 South Africa, South America, and Europe, is more especially char- 

 acteristic of the cosmopolitan Jurassic floras. 



The Arthrophyta of the Triassic were less varied than earlier. 

 The order Sphenophyllales as well as the majority of the calamites 

 had become extinct, but representatives of the latter continued to 

 exist throughout the Triassic, where they were represented by Schi- 

 zoneura and Phyllotheca which survived from the Permian and by 

 Neocalamites (fig. 35) which occurs in the Upper Triassic of 

 Virginia, Mexico, Europe, Asia, South Africa, and Australia. In 



Fig. 33.— Restoration of DIrtyophyllum (after Nathorst), X 1/2. 



addition to these, the remains of large species of Equisetum are com- 

 mon as stem casts in the continental deposits of the Triassic. 



The Lepidophytes were represented during the Triassic by oc- 

 casional fragments of Lycopodites (Xaiadita) like foliage, and in 

 the Lower Triassic by a few specimens of Sigillaria and a related 

 genus known as Pleuromeia, which testify that this characteristic 

 Permian type still lingered, although much reduced in importance. 

 Xo lepidodendrons are known from the Triassic unless represented by 

 the cone genus Lycostrobus from the Upper Triassic of Sweden. 

 The Pteridosperms or seed ferns, so important and characteristic 

 an element in Paleozoic floras had largely vanished. Triassic sur- 

 vivals probably existed although none are certainly known. Glos- 

 sopteris, which gives its name to the Permian flora of Gondwana 



136650°— 20 26 



