There are sailors’ eyeballs to be found at sea, that is, if you know where to look. Fortunately not the result of any gouging injuries, these curious blobs are a type of algae called Valonia ventricosa , and they’re one of the largest single-celled organisms on Earth. The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.
The size of sailors' eyeballs can vary from a speck the size of a pinhead to, well, an eyeball. Just how big the blob gets all comes down to the contents of its vacuole – the space inside its cell wall.
V. ventricosa is unicellular, but it can contain the nuclei of many cells. This is because they’re coenocytic organisms , meaning they’re made up of a mass of cytoplasm containing many cell nuclei that aren’t separate

IFL Science
Insider
HowStuffWorks Animals
CBS News
Just Jared
ABC 7 Chicago Entertainment
Raw Story
The Daily Beast