§ 43. SUCCESSIVE CHANGES IN THE ORGANIC KINGDOMS. 883 



in mollusca, radiaria, and Crustacea, of genera and species, 

 unlike any that previously appeared. 



We advanced to other oceans (the JPalceozoic), swarming 

 with polyparia, mollusca, radiaria, and fishes, which bore 

 some analogy to those of the preceding seas, but belonged 

 to different genera : and containing interspersions of cryp- 

 togamous plants, and relics of a terrestrial flora related to 

 the carboniferous. But as we proceeded in a descending 

 order, traces of animal and vegetable existence became 

 less and less manifest, and were at length reduced to a 

 few shells, corals, and sea-weeds ; these finally disappeared, 

 and dubious vestiges of infusoria were the last indications 

 of organic life. 



43. Successive changes in the organic kingdoms. 

 — If we reverse the order of our retrospective survey, and 

 pass in succession from the most ancient to the modern 

 deposits — from the regions of sterility and plutonic action, 

 to those in which animal and vegetable life were profusely 

 developed — we obtain the following results : — 



Geological For- 

 mations. 



Character of the Fossil 

 Fauna. 



Hypogene rocks . Infusoria i 



Character of the Fossil 

 Flora. 



[ No traces of vegetable 

 I matter. 



Cumbrian 

 system 



Silurian 

 system 



(Corals and shells, (brachio- ) 

 poda) } Fucn 



(Corals, crinoidea, orthocera, 



I and other shells ; Trilobit.es, 



' V Fishes 



I Corals, crinoidea, cephalo- 

 poda, shells, both marine 

 (chiefly brachiopoda) and 

 . fresh-water; trilobites. In- 

 sects, sauroid Fishes, Rep- 

 tiles ? Birds ??? . . . . 



Fuci. 



Many hundred spe- 

 cies of plants ; the 

 vascidar cryptoga- 

 mia largely deve- 

 loped. Palms, tree- 

 ferns, coniferae. Di- 

 cotyledonousplants 

 very rare. 



VOL. II. 



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