FOOD OF FISHES 67 



faint traces of attenuated Yicrht at this depth — green plants 

 cannot hve, and there the animals are necessarily dependent 

 on each other for their food. They are all carnivorous, and the 

 deep sea fishes have tremendous jaws with rows of vicious-look- 

 ing teeth with which they catch their prey. Down in the depths 

 of the ocean one realizes how right the Frenchman was who 

 said that life was summed up in the conjugation of the verb 



"manner"; ^ 



^ Je mange, 



Tu manges, 



II mange, 



Nous mangeons, 



Vous mangez, 



lis mangent, 



or its terrible correlative : 



Je suis mange, 



Tu es mange, 



II est mange, 



Nous sommes manges, 



Vous etes manges, 



lis sont manges. 



Sharks and dogfish are Avell known to be carnivorous, and 

 the former often attack man. A good many fishes live upon 

 their kin, though the cod varies its fish diet by eating Crus- 

 tacea, and the haddock chooses as its food such invertebrates 

 as starfish, sea-urchins, and Crustacea. The plaice and flounder 

 and other flat fishes devour molluscs such as cockles, clams 

 and mussels ; and the sole consumes worms. The fishes which 

 live chiefly on floating Copepods and small Crustacea fre- 

 quently have comb-like processes inside their gill arches. This 

 is true of the basking shark, Cetorhinus, one of the largest 

 of fishes, 40 ft. in length, and also of the herring. The 

 processes act as a sieve, sifting out the Crustacea from the 

 water which enters the mouth and then flows out over the 

 gills. A few fishes browse upon the seaweed growing round 

 the coast, whilst sardines, the young of the pilchard, are also 

 herbivorous, living upon the diatoms which they sift from 

 the surrounding water much in the same way that the herring 

 sifts its copepods, or the whale-bone whale its floating molluscs. 



5-a 



