What is "watermelon-shaped"

Usage examples of "watermelon-shaped".

Willis proceeded to change his shape, until he was more nearly watermelon-shaped than globular.

I drove on across New York State for several hours, through the Susquehanna Valley, which was very beautiful, especially at this time of day and year in the soft light of an autumn afternoon: watermelon-shaped hills, golden trees, slumbering towns.