FAUNA AND FLORA. 



18 



abundant proofs to the contrary, and naturalists had found many animal forms 

 below the limits assigned to them by the learned explorer. ^Nevertheless such 

 testimony had not received all the attention it deserved, and the triumphant 

 scientific expeditions of the Lightning and Porcupine were needed before the 

 previous labours of Ross, Wallich, Sars, Fleemiug, Jénkin, and Milne-Edwards 

 could be regarded as definitely secured to science. At all their sounding stations 

 Carpenter, Wyville Thomson, "and Gwyn Jeffreys found the ocean bed covered with 

 animal organisms. In the great troughs of the Spitzbergen seas Torell had also 

 found such organisms in prodigious quantities, far superior in the wealth of their 

 forms to those of the Scandinavian seaboard. Even at the depth of 2,700 fathoms, 



Fig. 8. — Zone of the Cold Waters in the North Atlantic. 



Eeptb to 547 

 i'athoms. 



547 to 1.034 

 Fathoms. 



the lowest reached by the plummet, the Arctic Ocean possesses a fauna of many 

 species. The explorations have but slightly increased the number of fishes known 

 to science, but the museums have been enriched by many new echinoderms, some 

 yerj curious and extremely beautiful, and Wyville Thomson alone has been 

 enabled to describe 250 new species of molluscs. On the other hand, the limits of 

 the marine flora have remained unchanged. Beyond 50 fathoms the algoo become 

 rare, disappearing altogether at a depth of 200 fathoms. 



The wealth of the fauna is all the greater in the northern seas of Euroj)e 

 because their waters flow from different climatic regions. The currents of w^arm 

 water form-ng the upper strata bring with them southern organisms, while the 



