318 
THE OCEAN WORLD. 
aggregation of individuals. Each solitary Biphora engenders a ne" 
group — a chain ; each constituted member of the chain engenders a 
solitary Salpa. 
Thus a Salpa is not organized like its mother or daughter, b n 
rather like its sister, its grandmother, or granddaughter — another 
example of alternate generation, which has already been discussed 111 
treating of zoophytes. 
Those marine creatures which pass their lives in a forced community 
— animals which eat, sleep, or rest always in company — who abandon 
themselves together to the soft caresses of the waves, — these colon 16 "' 
or, rather, republics of animals, leading constantly the same mono 
tonous existence, — reveal to us very strange things : an identical conn 
munity of sentiments in a crowd of beings riveted by the 
chain — a chain at once physical, intellectual, and moral ! 
He who has never brought his attention to bear upon the history 
of the inferior animals is a stranger to many surprising mysteries > 
in short, the study of natural history is the best means of adding t0 
and extending the knowledge and ideas of the young. 
