That is a cute baby and he/she looks adorable in the cocoon. It does look like a long hat to me, too.
All that said I would NOT put a baby in one of these.. my experience with babies (my own 2) tells me that their diapers often don't hold what they are supposed to and can you imagine trying to take that off.. Gah!

As cute as this is I think blankets are better or some sort of wrap that has a strap or tie if you want it secure.