.\}frnnu.\xs of the com. swamps wy.) 



they \vci-(' ;iiii])liil)i()iis ;iiiiiii;ils, liall' i-cptilc. Ii;ilt' (isli, in a|)|)c;ir;iiicc ;iii(l 

 habits. 



Li\iiiU' ;iin|)liilM;i ;irc the sur\i\(»rs more or less altered of llie kind of 

 animal which in the (Oal l-',fa was the liii^jiest t'onn of animal life. The 

 study of the stnieture and d('\cloi)ment of the lii<;lier xcrtehrates of 

 reptiles, l)ii(ls and mammals — has shown that they must he deri\'ed from 

 animals of this typi'. and the successive stages in tluMr e\()lutioii are illus- 

 trated hy the fossil vert(>l)rates of the successive periods of geoloiiical history. 

 In the Carboniferous tiie am|)hil)ians were the dominant type, and the 

 reptiles were just benimiing to e\()l\-e from tluMu, becoming adapted to a 

 more strictly terrestrial life. These earliest reptiles are very close to the 

 primitive amj)hil)ians, and the wide gap that now separates these two 

 classes of vertel)rates was then .so slight that it is difficult to draw any sepa- 

 rating line between them. 



Most of the primiti\e amphibians are so small and their skeletojis so 

 crushed and imperfect that they cannot very easily be studied except by 

 specialists. A few of them however, the giants of their day, are of fairly 

 large size, and well ])res(M'ved skeletons ha\e been found in the "red beds" 

 which innnediately ox'erlie the coal formation of Texas and are of somewhat 

 later age (Lower Permian) than the true coal measures. Kri/ops is the 

 largest and best known of these Permian amphibians in America. Its 

 bones have been found in the upper coal measures of PennsyKania but the 

 best skeletons are from the Texas red beds. 



Here then is the type of animal that lorded it oxer the denizens of the 

 gloomy forests and dark morasses of the Coal Period: a sort of gigantic 

 tadpole or mud ])uppy, with wide flat head, no neck, a thick heavy body, 

 short legs and ])addle-like feet and a heavy flattened tail. While able to 

 crawl clumsily and slowly upon th(> land, he must lia\'e been far more 

 at home in the water, living in the dead pools and backwaters and slow- 

 moving streams that traversed the far extended coast-marshes of the great 

 interior sea to the west of the Appalachian highlands. 



That this beast, slow, hea\y and clumsy, small brained and low organ- 

 ized, should be one of the highest types of living beings in his time, may 

 help to realize how remote and far away was the era of the Coal Forests. 

 That he is a collateral ancestor of all the higher animals — of reptih^s, birds, 

 manunals and of man himself — all evoKcd through the millions of years 

 which have since elapsed from animals of the same type and grade of 

 organization, may serve at least to rai.se our resjx'ct for the possibilities of 

 development which lay in the primitive ami)hil)ia. The giant dragon fly 

 that darted over the head of the sh)w-crawling Eryops might seem, e\eej)t 

 in size, a far superior type of Ix-ing, a far more ])r()mising candidate for the 



