USPS Cover Cranes, Project Mercury, American Legion and Wonders of the Sea

USPS cover shown here has a block of four 29-cent postage stamps issued on 4 April 1994, featuring the Whooping Crane and Black-Necked Crane.

Additionally, two 4-cent postage stamps commemorating Project Mercury, the first human spaceflight programme of the United States. Issued in 1962, the stamp features the Mercury spacecraft (which was involved in six manned flights) is set against a backdrop of the Earth and stars. 

Shown on this cover are also two 6-cent postage stamps issued on 15 March 1969 to commemorate the 50th anniversary of the American Legion. The design depicted an adaptation of the bald eagle from the Great Seal of the United States, clutching an olive branch. The text "The American Legion," "50 years," and "Veterans as Citizens" are also prominent.

Lastly, a 29-cent postage stamp issued in 1994 was part of the "Wonders of the Sea" series. Depicted here is a vibrant coral reef scene with various fish species, including angelfish and clownfish