500 THE CHEMISTRY OF CKEATION. 



one or two of the eight zones, while only two 

 species are common to them all. It is remark- 

 able, however, that the first zone or coast- 

 region, extending to the depth of two fathoms, 

 contains a greater number and variety of crea- 

 tures than any of the rest, or indeed than all the 

 others put together. The lower zone contains 

 fewer animated beings, and on its confines, at the 

 depth of 230 .fathoms, or at most at that of 300 

 fathoms, animal life ceases in the Mediterranean. 

 The remarkable fact has been already mentioned, 

 that as the depth of this sea increases, and the 

 same laws prevail in other seas which have 

 undergone similar investigation, the marine 

 animals occupying the deeper regions assume 

 more and more the characters of those found in 

 northern climates. The occupants of the coast 

 zone represent properly the peculiarities of form 

 and colour characteristic of the inhabitants of 

 southern latitudes. The sea thus, as we examine 

 its depths, presents us with a sort of map repre- 

 senting types of the occupants of the seas of 

 other climates. The more deeply the shell- 

 fish is found down, the more to the north 

 will lie the place where its allies are dwellers 

 on the coast. The coast zone shows the marine 

 inhabitants of the latitude of the region, the 

 lower zones those of higher latitudes. 



While a considerable number of the dwellers 



