770 



THE AMERICAN NATURALIST [Vol. XL, 



1837. Charles Lyell' gave the note for modern methods of re- 

 search, greatly influenced Darwin, and perhaps exaggerated imi- 

 formitarianism. 



In this very problem of extinction, however, uniformitarianism 

 has a stout opponent in Henry H. Howarth. In his extremely 

 interesting work The Mammoth and the Flood (London, 1878) he 

 revives the theory of the destructive flood and marshals a vast 

 number of facts to its support. "These facts," he observes (p. 

 xvii), "I claim prove several conclusions. They prove that a 

 very great catastrophe or cataclysm occurred at the close of the 

 Mammoth period, by which that animal, with its companions, 

 were [!] overwhelmed over a very large part of the Earth's sur- 

 face. Secondly, that this catastrophe involved a very widespread 

 flood of water, which not only killed the animals but also buried 

 them under continuous beds of loam or gravel. Thirdly, that the 

 same catastrophe was accompanied by a very great and sudden 

 change of climate in Siberia, by which the animals which had pre- 

 viously lived in fairly temperate conditions were frozen in their flesh 

 under ground and have remained frozen ever since." 



The causes enumerated by Lyell in his later edition of the Prin- 

 ciples of Geology after the publication of Darwin's Voyage and 

 Or'ujin arc: (1 ) competition as affected chiefly by the introduction 

 and extrusion of new forms, (2) agency of insects, e. g., caterpillars, 

 ants, locusts, in favoring or checking increase of plants and thus 

 att'ecting the food supply of animals, (H) intimate reci};r()cal rela- 

 tions of animals and plants in the delicate bahuice of food supply, 

 (4) disturbance of the equilibrium (/:• La'atue of nature by the 

 introduction of new insects, plants, vertebrated animals, (5) 

 changes in [)liysi( al ;^-eo(ria|)liy affecting zoological and botanical 

 provinces \)\ new land or water connections, facilitating introduc- 

 tion of new conipetinL;- forms. Mi) causes especially potent in island 



^.■fen-ing t.> that snl.ll,' a.ljustnient of the .,nn of all int.-rnal 

 an<l external ean>e> .ailed the hnlnnrrnj nnlurr, Lvell' ol.^erved: 

 "Kv.-ry new conditio!, in the >tate u( the organic or inorganic 



pp. 455- 



