ISO 



THE CHAIN OF LIFE. 



look more like those of the latter ; and this seems to be a 

 common character of two or three others of the few fossil 

 species known, none of which are older than the Tertiary. 



We know too little of the spiders and scorpions of the 

 Carboniferous to say more than that they closely resemble 

 modern forms. One of the scorpions is represented in Fig. 132 ; 

 and the only spider certainly known, which is from Silesia, is 

 said to belong to the group of the hunting or trap-door spiders 

 [Lycosa)} 



The Batrachians of the Coal are its most characteristic and 



Fig. 131. — Pi.\\YiOCGncV>\MQxAy {Proiityas perseJ>hoHe, Scudder). From Colorado. 



remarkable air-breathers, — especially so as the precursors of the 

 reptiles of the Mesozoic age. Cope in a recent summary 

 enumerates no less than thirty-nine genera and about one 

 hundred species ; and to these have to be added at least a 

 dozen more recently discovered in Europe ; though it was 

 only in 1841 that the first indications of such creatures were 

 found, and were then regarded by geologists with the same 

 scepticism which some of them still apply to Eozoon. The 



* Protolycosa (Roemer). 



