TRIASSIC PERIOD. 



425 



(1. Werfen beds, shale, sandstone, gypsum, salt. 

 2. Guttenstein beds, shale and limestone 150 feet. 

 3. St. Cassian beds, red, pink, and white limestone, at St. Cas- ) n^ * t 

 sian and Hallstatt ' 



(4. Dachstein beds, white and grayish limestone 2,000 feet. 



B < 5. Kossen beds (Bhcetic of Giimbel, Upper St. Cassian of Escher 



' and Merian), gray and black limestone and marls ... 50 feet. 



The Werfen beds are regarded as corresponding to the Bunter-sandstein; the Gut- 

 tenstein, to the Muschelkalk and Lower Keuper; the St. Cassian, to the Middle 

 Keuper; the Dachstein and Kossen, to the Upper Keuper. The Kossen beds are the 

 Rhsetic beds of Giimbel, and are by some referred to the Lower Lias. The St. Cas- 

 sian beds of St. Cassian and Halstatt (between the head waters of the Inn and Drave, 

 the former on the south, and the latter on the north side of the Austrian Alps), are 

 remarkable for containing, among the 600 species of invertebrate fossils, many of 

 Paleozoic genera, some of them not found elsewhere above the Permian. The Rhretic 

 group in England (called the Penarth in the Government survey) includes beds of 

 "the Avicula contorta zone", between the Trias and Lias. They occur in Dorset, 

 Somerset, and Warwick to Lincolnshire. They include the "White Lias" of Wm. 

 Smith, and the " landscape marble " of Cotham, near Bristol; and, next below these, 

 black paper shales, with many fossils and a bone-bed, and then marlytes, mostly 

 -without fossils. The St. Cassian Series is sometimes called the " Alpine Trias." 



II. Life. 



The European Triassic beds have afforded teeth of one species of 

 mammal, but fail of relics of birds. 



1. Plants. 

 Equiseta, Ferns, Cypress evergreens, and Cycads (Fig. 739) are 



Figs. 737-739. 



739 



Tig. 737, Voltzia heterophylla ; 738, one of its fruit-bearing branches ; 739, Pterophyllum Jsegeri. 



the prevailing forms. No true Grass, Moss, Palm, or Angiosperm 

 has yet been found in beds of this period. 



Characteristic Species. 

 Figs. 737, 738, parts of branches of the Voltzia heterophylla Brngt., of the Cypress 



