CHAPTER XIII.

Animal life of the Carboniferous period--Protozoa--Corals-- Crinoids--Pentremites--Structure of Pentremites--Echinoids-- Structure of Echinoidea--Annelides--Crustacea--Insects-- Arachnids--Myriapods--Polyzoa--Brachiopods--Bivalves and Univalves--Cephalopods--Fishes--Labyrinthodont Amphibians-- Literature.