ABSENCE OF PLANT LIFE 43 



ness, or at most to an intermittent ''phosphorescent" 

 shine of no great brilliance. 



On first consideration, it would seem as if the 

 absence of plants must be an interdiction of more than 

 pontifical potency on animal life ; and such indeed 

 would be the case, if there were not an abundant out- 

 side supply of food derived in the last resort from 

 the vegetable kingdom. This outside supply may 

 come either from the rivers, which must wash an 

 enormous amount of organic matter into the depths ; 

 or from the surface of the ocean, where of course the 

 creative interaction between the animal and vegetable 

 kingdoms is in vigorous progress, and must at last 

 lead to a perpetual shower of dead stuff, suitable for 

 food, into the abysses beneath. It must, further, be 

 remembered that there is no abrupt division between 

 deep and shallow, but that the depths are reached by 

 a series of slight overlapping gradations, and that 

 for this reason there must be a continuous gradual 

 circulation of organic matter between the shallow 

 zones of plant life and the deep regions of no - plant 

 life. But even when these three factors have been 

 duly considered, we shall expect to find that the depths 

 near the continents are more prolific than the far-off 

 abysses of the open ocean ; and this appears to be 

 actually a fact. For although animals have been 

 brought up from the greatest depths to which the 

 dredge has been lowered, yet if one expects to get a 



