24 



THE NATURAL HISTORY OF 



suddenly rise from the salt into the fresh water, be 

 as suddenly paralyzed, and precipitated in their con- 

 vulsed attitudes into the abyss below, where, sinking 

 rapidly in the soft mud of the sea-bed, their remains 

 would become enveloped and potted, before the 

 numerous animals that creep and swim, watchful 

 for carrion everywhere in the habitable depths of 

 the ocean, had become aware of the neighbourhood 

 of such acceptable prey. 



The influence of depth is everywhere manifest in 

 the European seas, for everywhere we find creatures 

 whether animal or vegetable, distributed in succes- 

 sive belts, or regions, from the margin of the high 

 water-mark, down to the deepest abysses, from 

 which living beings have been extracted. Peculiar 

 types inhabit each of the zones in depth, and are 

 confined to their destined regions, whilst others 

 are common to two or more zones, and not a few 

 appear to have the hardiness to brave all bathy- 

 metrical conditions. Nevertheless, so marked is 

 the fades of the inhabitants of any given region 

 of depth, that the sight of a sufficient assemblage of 

 them from some one locality, can enable the natu- 

 ralist to speak at once to the soundings within 

 certain limits, and without the aid of line or plum- 

 met. Throughout the oceanic portion of the seas 

 of Europe, four distinct and well-marked zones of 

 life succeed each other. The first of these is the 

 littoral zone, equivalent to the tract between tide- 

 marks, but quite as manifest in those portions of 



