Hemispheres, plane and paddle steamer (Aden 1949)

Stamp Hemispheres, plane and paddle steamer it reflects the thematic directions:

These clams live buried in the sediment on tidal flats. While they are common in muddy areas, their name "arenaria" means sandy and they prefer a combination of sandy and muddy areas. They are well known as a food item on the coast of New England in the Western Atlantic Ocean; however, the range extends much farther north to Canada and south to the Southern states. They are also found in the Eastern Atlantic Ocean, for example in the UK, as well as in the North Sea's Wadden Sea (where they are the dominant large clam). 

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Aviation is the practical aspect or art of aeronautics, being the design, development, production, operation and use of aircraft, especially heavier than air aircraft. The word aviation was coined by French writer and former naval officer Gabriel La Landelle in 1863, from the verb avier (synonymous flying), itself derived from the Latin word avis ("bird") and the suffix -ation.

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