despite the accumulations of humus over a period of many years; 

 therefore "blowouts" can occur at any time returning the area to 

 sand, and the cycle begins again. 



AUDIENCE: High school; college 



THE TROPICAL RAIN FOREST 



Color Sound Encyclopaedia Britannica Films, Inc. 



17 minutes Rental Sale 



Since the tropical rain forest contains the largest variety of plant 

 and animal life of any biome, it is hard to describe in a short film. 

 This particular one represents the outstanding effort on the topic 

 to date. The layered structure of vegetation is clearly portrayed 

 through the use of drawings and photographs. The conditions of 

 soil, temperature, and moisture peculiar to this area are also well 

 presented. Comparison to the temperate deciduous forest with which 

 more students would be familiar helps to explain this particular 

 forest. 



In depicting the fauna little time is spent on the larger animals 

 relatively unimportant in the system; principal attention is given 

 to the dominant animals of each layer birds, monkeys, and the 

 most numerous of all, the arachnids of the forest floor. 



The film is distinguished by some unusually fine photography 

 and the judicious use of natural sounds. 



AUDIENCE: High school; college; adult 



WHAT IS ECOLOGY? 



Color Sound Encyclopaedia Britannica Films, Inc. 



11 minutes Rental Sale 



As an introduction to the study of ecology, this film is both brief 

 and thorough. The basic concepts of the subject are presented 

 through the introduction of the major biomes of the world with 

 brief descriptions of environmental characteristics including typical 

 plants and animals. Titles superimposed over these sequences point 

 out the applications of ecology's specialized terms. 



The study of ecology is given its proper importance from the 

 opening scene. An auction of a farmer's machinery and household 

 effects is in progress; he failed because he did not consider eco- 

 logical principles in his farming. Shots of the dust bowl and the 



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