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the present coast of Portugal. This latter species is 

 clearly of a more adaptive nature than its allies, inas- 

 much as it has, also, naturalized itself (though this may 

 be a more recent, and accidental, circumstance) on the 

 opposite shores of Africa. One thing, however, is at any 

 rate manifest, that the Hegeters attain their maximum 

 in the Canaries, and that a few members only have been 

 sent oif, in a northerly, or north-easterly, direction, 

 from thence. 



In like manner, the genus Tarphius is distinctively 

 Madeiran. I have detected nearly twenty well-defined 

 species of it in that group; yet, out of so large a 

 number, two only have occurred beyond the central 

 island. Now the Tarphii are, also, wingless ; and crea- 

 tures of very sluggish propensities, scarcely ever stir- 

 ring from the masses of loose rotting timber which they 

 so assimilate in hue, and to the under sides of which 

 they affix themselves, day and night. Although difficult 

 to investigate in their precise economy, it is extremely 

 probable (may I not say, certain ?) that some important 

 and peculiar office is assigned to them in the remote 

 upland districts to which they exclusively belong : and 

 there cannot be any question, to a person who has 

 studied them carefully on the spot, but that the region 

 which they now inhabit is the actual area of their prim- 

 aeval appearance on this earth. Many kindred species 

 may of course have been lost, during those gigantic 

 subsidences which caused the Madeiras to be shaped 

 out, and to tell their tale above the waves as ruins of an 



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