Handbook of Paleontology 423 



abundant. Large, shell- feeding sharks developed rapidly 

 and many kinds of amphibians existed. The plant life 

 was much as in the Pennsylvanian. 



The marine life of the Pennsylvanian period, like that 

 of the preceding, was varied. The spiny brachiopods 

 (Productus) were abundant and were the commonest of 

 the shelled animals, though pelecypods were becoming 

 more and more abundant. Foraminifera for the first 

 time were abundant and varied (Fusilina,) as also in late 

 Mississippian. While brachiopods were declining the 

 goniatite and ammonoid cephalopod stocks were rapidly 

 developing. Trilobites and eurypterids became extinct in 

 the Pennsylvanian. Land snails appear in this period. 

 Insects are present in giant form and because of the 

 abundance of cockroaches the Pennsylvanian is known as 

 the Age of Cockroaches. Scorpions and spiderlike ani- 

 mals are found and myriopods or thousand-legged worms 

 are plentiful. Among the fishes only sharks and typical 

 ganoids were important, and the number of sharks had 

 become very small before the close of the Pennsylvanian. 

 Among land animals there were many kinds of amphibi- 

 ans inhabiting the coal swamps, and reptiles appeared in 

 the Upper Pennsylvanian. The land plants of the Car- 

 boniferous, particularly the Pennsylvanian or Coal Meas- 

 ures, consisted of ferns (including tree ferns), seed ferns, 

 club mosses or lycopods, horsetails (calamites) and some 

 gymnosperms (Cordaites etc.). (See part 1) 



The marine life of the Permian is a modification of 

 Pennsylvanian faunas. Insects are greatly changed in 

 this period. They have become smaller and more mod- 

 ern. The reptiles of the Permian are even more varied 

 than the amphibians. America has by far the richest and 

 most varied fauna of Permian vertebrates. 



