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1. Development of the axolotl (08:35)

Date:
1977
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Summary:
Studies the early stages of the development of the axolotl, an aquatic salamander, with emphasis upon genetically determined characteristics. Mates two wild-type, dark axolotls, each heterozygous for white and albino mutations. Uses time-lapse photography to show cleavage to the blastula stage, gastrulation, and neurulation. Observes rotation and elongation of the embryo, followed by identification of the gills, somites, and eyes. Records as the embryo breaks free of the vitelline membrane. Shows the well-developed gills, heart, and eyes in a later state. Concludes by showing the dark, golden albino, white, and white albino larvae.

2. Land use on the flood plain (17:09)

Date:
1975
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Summary:
Examines the relationship between flooding and land use. Explains that the proximity to transportation, energy, and fertile soil has often outweighed the dangers of flood, and offers dams, levies, and flood-plan zoning as methods of controlling land use on flood plains.

3. The land along the water (10:22)

Date:
1969
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Summary:
Characterizes the land that lies along oceans and large lakes in terms of physical features and uses of the land. Points out that differences in the physical appearance of land near shorelines may be caused by natural forces such as wind and erosion, or by man building inland waterways and constructing recreational facilities. States that nature sometimes ruins what man has built, but that man often destroys the beauty of land that nature has taken a very long time to develop.