116 THE FAR PAST. 



We now close the long record of Ancient Life, during 

 which whole races and families departed, and others took 

 their place the march of vitality being ever forward to 

 higher and higher orders. We have seen that all the great 

 types of life radiate, molluscan, articulate, and verte- 

 brate had their beginning simultaneously and indepen- 

 dently on the globe, and that all subsequent progress has 

 been restricted to the modification and elimination of these 

 primal patterns. We have seen the graptolites of Siluria 

 rise, culminate, and depart with that period ; seen also its 

 curious encrinites and foot-stalked sea-urchins, or cystidecp., 

 flourish and die within the same limits ; and witnessed its 

 wonderful flush of trilobite life, which waned in the old red, 

 and finally disappeared about the middle of the carbonifer- 

 ous era. So also have we witnessed the larger crustacean 

 forms of eurypterus and pterygotus come strongly and 

 forcibly on the Devonian stage, and somewhat speedily 

 wane and die out with the coal period, during which other 

 forms, prefigurative as it were of the existing limulm, take 

 their places. In like manner the curious bone-clad fishes 

 of the old red (the " palichthyan" aspect of fish life) rise 

 and depart with that system only a few of the genera, but 

 none of the species, living into the carboniferous epoch. 

 And when we come to the coal period itself, there also all 

 the wonderful and exuberant forms of its vegetation its 

 stigmaria, sigillaria, lepidodendra, bothrodendra, catamites, 

 and tree-ferns start into being, nourish in profusion, and 

 depart with those physical peculiarities which stamped 



glaciers of the Vosges, Wales, Ireland, and the Highlands of Scotland ; 

 or like many stones in the pleistocene drifts. 4. A hardened cementing 

 mass of red marl, in which the stones are very thickly scattered, and 

 which in some respects may be compared to a red boulder-clay, in so far 

 that both contain angular, flat-sided, and striated stones, such as form the 

 breccias wherever they occur. Journal of Geological Society, vol. xi. 



