168 THE OLD COAL-MEASURES. 



such names as catamites (reed-like), equisetites (equisetum- 

 like), lycopodites (clubmoss-like), sphenopteris (wedge-leaf 

 fern), neuropteris (nerve-leaf fern), lepidodendron (scaly- 

 bark tree), bothrodendron (pitted tree), and so forth, all 

 pointing to some obvious feature which distinguishes them 

 one from another, but throwing very little or any light on 

 their true botanical affinities. But whatever their strict 

 affinities, we know that most of them belonged to the lower 

 orders of vegetation the horsetails, ferns, and clubmosses, 

 the grasses, sedges, and rushes, the cycads and pine-trees, 

 or perhaps more properly to extinct forms that stood inter- 

 mediate, as it were, between these various orders. Though 

 lowly in organisation and most of them were undoubtedly 

 so they seem to have occupied large areas of the earth for 

 ages, and to have grown in rank luxuriance, till in numer- 

 ous instances their accumulated masses form seams of coal 

 from a few inches to many feet in thickness. 



When we turn to the Fauna of the period, we find 

 throughout the same variety and the same numerical abun- 

 dance, though, of course, certain forms are more abundant 

 in one portion of the system than in another. These forms, 

 too, are chiefly aquatic fresh- water, estuarine, and marine j 

 there being few terrestrial species yet discovered, and these 

 only at wide intervals and in few localities. Beginning with 

 the lower forms, we have a number of minute foraminiferal 

 organisms, and a vast exuberance of corals and encrinites, 

 so vast that beds of the mountain limestone, hundreds of 

 feet in thickness, are almost entirely made up of their 

 remains. There are also trails, burrows, and tubes, that 

 indicate the existence of marine annelids ; abundance of 

 crustaceans, some minute and bivalved like the cypris, a 

 few species of trilobites, and others like the king-crab, and 

 of large dimensions. The polyzoa or flustra-like organisms 

 occur too in great variety, scattering their netted cells 



