Ok, so I will admit, I originally thought Benito Cereno was a short story, which is pretty silly because it's so long. The other day a friend of mine said something about Benito Cereno being a Novella so I had to check it out. I don't think I've even heard of that before, but anyways, here it is.
The Novella falls between the vovel and the short story in both length and complexity. A particular novella may be substantial enough to be published in a seperate volume, like a novel or included in a collection of works.
So if you ever wonder why your short story is so darn long, it's possibly a novella instead.