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Our Surroundings 



Everyone is familiar with the common bath sponge. Sponges 

 grow on the sea bottom in various warm sections of the world, 

 especially in the Mediterranean and the Red Sea and in the ocean 

 around the West Indies and Florida. They are gathered in great 

 quantities, dried, and prepared for the market. The annual value 

 of the sponge crop amounts to several million dollars. 



Corals are small but very numerous animals living in clear 

 sea water of moderate depth. Since they live in enormous colonies 

 their limy skeletons in time form great reefs. Many islands in 

 the Pacific ocean and parts of some continents originated from 

 coral reefs. Coral rock is often beautiful in color and is made 

 into ornaments of various kinds. 



Mollusks, especially oysters, clams, mussels, and scallops, have 

 always been a source of food for man. Their shells are 

 used as material for making buttons, knife handles, and orna- 

 ments of various kinds. Even the cuttle-fish furnishes cuttle bone, 

 a limy substance used to make polishing powder. Cuttlebone is 

 often placed in bird cages to supply birds with needed lime and salt. 

 Cuttlefish also supply sepia, a rich brown liquid used by artists 



for coloring. 



Insects. When plants are in 

 flower they are constantly 

 visited by bees and other insects. 

 These insects are not there for 

 pleasure. They are seeking ma- 

 terial for food. Bees secure the 

 nectar of flowers and manufac- 

 ture it into honey which they 

 store for future food. Man, tak- 

 ing advantage of their indus- 

 try, secures the results of their 

 work for his own profit. While 

 getting this food material, in- 

 sects unconsciously render a 

 great service to plants and also to man, for they carry on 

 their bodies, from flower to flower, the precious powder called 

 pollen without which plants cannot develop fertile seeds. Bees, 



BEES COLLECTING NECTAR AND 

 POLLINATING FLOWERS 



