408 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1941 



merits continue for some time in the surrounding fluid. The zoo- 

 spores become fixed to a submerged object where they proceed to 

 develop cells and grow into algae similar to the ones from which they 

 originated. 



NATURE'S UTILIZATION OF ALGAE 



Now when algae are used in myriad ways in food, agriculture, in- 

 dustry, medicine, photography, and even in cosmetics, it seems strange 

 that, considering the great quantity of them growing all over the 

 world in the ocean as well as in fresh water and on land, their full 

 usefulness has been so slowly realized by man. Wise old Mother 

 Nature has always allotted them their role in her scheme of life 

 although man has been tardy in recognizing it and in applying her 

 methods of their utilization to his own needs. 



The great abundance of algae in the sea and on the land is not 

 merely an indication of nature's generosity. The microscopic and 

 visible algae that fill the ocean are there for a direct purpose whether 

 man sees fit to utilize them or not. For the oceans are teeming with 

 animal life varying in size from microscopic polyps to the mam- 

 moth whales which could not exist without the aid of the plant life. 

 One of nature's many laws is that animal life requires nutriment pre- 

 pared by the plant life, and plants are necessary to change the min- 

 eral constituents of their surrounding environment into available nu- 

 triment for the animals. In the sea, the algae are the only plants that 

 can grow and therefore a large number of species of sea animals are 

 directly dependent upon them for their food, while other species 

 depend upon them indirectly. The algae are indispensable to the 

 continuity of animal life in the sea. The green fat of the turtle and 

 the green material present in the lobster are indicative of their source 

 cf nourishment — the algae. 



There is a famous Chinese proverb : 



Big fish eat little fish 

 Little fish eat shrimp 

 Shrimp eat mud. 



The so-called mud is full of microscopic algae. The alimentary can- 

 als of small and large fish have long been happy hunting grounds 

 for biologists. The unicellular algae and diatoms are the salad of 

 the water. They are so minute as to be available for the consump- 

 tion of the smallest animal organisms, and yet, because of their 

 abundance, they may represent the sole food supply of some of the 

 larger forms of fish. They are highly nutritious, and not one among 

 the thousands of living species is deleterious. The abundance of 

 the plant growth in the water is responsible for the abundance of the 

 fish supply. Dr. Albert Mann, the noted diatomist, examined the stom- 

 ach contents of some young hake (fish about 5 inches in length). 



