466 



PENNSYLVANIAN PERIOD 



teeth it is inferred that they were predaceous. In Nova Scotia, 

 Dawson took thirteen skeletons of amphibians from a single sigil- 

 larian stump. Since land shells and myriapods are found in stumps 

 with the amphibian skeletons, it has been inferred that some of the 

 amphibians were climbers, and lived on mollusks, myriapods, and 

 similar land life. 



The amphibians of different continents were so similar as to 

 suggest great freedom of communication and migration, but free 



Fig. 402. CARBONIFEROUS TERRESTRIAL AND FRESH-WATER LIFE. Plants: 

 a, Calliptcridium mansficldi Lesq., b and c, Cattipteridium mcmbranaceum Lesq., 

 species of ferns. Land shells: d, Zonitcs priscus Carp., e, Pupa vcrmilionensis 

 Bradley. These land snails have been referred to genera living at the present time, 

 and although this reference may eventually prove to be incorrect, they are at least 

 close relatives of recent genera. Insects, etc.: /, Euphoberia armigcra M. and W., 

 a Carboniferous myriapod or thousand-legged worm; g, Eoscorpius carbonarius 

 M. and W., a scorpion very similar in type to living forms; h, Arthrolycosa antiqua 

 Harger, a spider more primitive than recent forms as seen by the segmentation of 

 the abdomen; i, Progonoblattina columbiana Scudd., one of the allies of the modern 

 cockroaches which were the most conspicuous members of the Carboniferous insect 

 fauna. Crustacea: j, Anthrapalamon gracilis M. and W., k, Palaocaris typus 

 M. and W., types of crustaceans found in the Mazon Creek nodules; /, Prcslwichia 

 dame M. and W., an early ally of the modern horseshoe crab. (Weller.) 



