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CELTIC PROVINCE. 



surface of the sea, and its bottom 150 fathoms deep, 

 extends for 30 miles, with a breadth of not more 

 than 2 miles. 



The floor of the Celtic province may be regarded 

 as an elevated platform with steep sides, deep iso- 

 lated pits and furrows, indenting bays and gulfs. 

 In its southern and western divisions this sub- 

 marine table-land supports a numerous population, 

 but that section of it constituting the bed of the 

 North Sea is comparatively thinly inhabited. The 

 deep parts of this latter portion, however, swarm 

 with fish and other animals. The little silver pit, 

 330 feet deep, may be cited as an instance. The 

 line of 100 fathoms may be taken as the southern 

 Celtic boundary. It pursues its course wavily and 

 with a general outward curve from off the coast of 

 Kerry to near the northern extremity of the Bay 

 of Biscay. The fifty-fathom line runs from Scilly 

 towards Ushant, with a deep inward sinuosity, and 

 between Scilly and the southernmost coast of Ire- 

 land makes a profound bend up St. George's Chan- 

 nel. The shallows of the inner extremity of the 

 English Channel are impediments to the spread of 

 many species. 



To the physical phenomena of the Celtic area, 

 and the geological changes it has undergone, are 

 due those varied features which its fauna and flora 

 present : warm currents from the south, cold cur- 

 rents from the north, coast-currents, and oceanic 

 currents, all converge to it as a centre. In their 



