ROMANCE OF DEPTHS OF THE SEA 115 



the abyss, ultimately depend for their food 

 supply. 



Then we have a second group of surface Plank- 

 ton which is composed of the larval-stages of 

 fishes, molluscs, star-fishes, sea-urchins, Crustacea, 

 worms, and many other groups. No matter 

 where these animals lay their eggs, their larvae 

 as a rule float to the surface of the water and 

 there drift hither and thither in incredible num- 

 bers. When one recalls the fact that the Right- 

 whale (Balaena), often fifty feet long, and one of 

 the largest agglomerations of flesh or proto- 

 plasm is nurtured on the drifting floating or- 

 ganisms, one appreciates the fact that the Plank- 

 ton forms indeed a very large feature in the life 

 of the sea. 



One of the most interesting contributions that 

 the " Michael Sars " has made to our knowledge 

 of this surface fauna is by Dr. Gran. He is 

 responsible for a comprehensive chapter on the 

 Phyto-plankton or the drifting plant-life of the 

 sea. Careful microscopic examination of the 

 bottom of the sea revealed a long time ago certain 

 calcareous rods and plates known as rhabdos- 

 pheres and coccospheres, little calcareous bodies 

 belonging to microscopic organisms. Systema- 



