646 GEOLOGY. 



gamopteris, N oeggeraihiopsis , and Neuropteris, the equisetales Phyl- 

 lotheca and Schizoneura, and the conifer Voltzia (Fig. 298, a-h), the 

 first two being eminently characteristic. The peculiar expression 

 of the group will at once be recognized, especially the simplicity of 

 the outlines of the fern leaves, and their contrast to the usual dissected 

 forms, as also the pauperate aspect of the Voltzia. These give support 

 to the view that this flora was evolved to meet the adversities of cli- 

 mate which prevailed in and about the glaciated regions. While the 

 fossils of this flora do not actually appear in the glacial beds them- 

 selves, they are found in tne interglacial deposits, and in those that 

 lie immediately above the upper glacial beds. Developed thus amid 

 adverse surroundings, if not directly under adverse conditions, the 

 flora not only took on a resistant aspect in simple outlines and com- 

 pact forms, but soon gave evidence of its vitality by spreading north- 

 ward into east Africa and Asia, and then Europe. 1 It reached northern 

 Russia in the latter part of the Permian period (Amalitzky), where 

 it was associated with Callipteris and other forms typical of the Euro- 

 pean Permian flora. It is also found in Brazil and Argentina. Its 

 vitality is further shown in that its descendents became a dominant 

 feature in the Mesozoic floras that followed. 



//. The Land Animals. 



The Amphibians. — Relatively, the amphibians reached their most 

 declared supremacy in the latter portion of the Carboniferous period, 

 and they may have been then actually at their numerical climax, for 

 the conditions were apparently extremely favorable for them. They 

 continued, however, to be a prominent feature in the early portion 

 of the Permian at least, but they probably declined in the later portion 

 under the less favorable physical conditions then prevalent, supple- 

 mented by the attacks of the predaceous reptiles that had entered 

 the arena. At any rate they were overshadowed in historical sig- 

 nificance by the rise of the reptiles, without doubt their descendents. 

 The Permian amphibians were of much the same types as before, 

 with some advances in organization, and some reptilian tendencies. 



The appearance of the primitive reptiles. — While the reptiles prob- 



1 Amalitzky, Schrift d. Warschauer natui\ Ges., 1895-1900. 



