"Something"

If you're using the iPhone app (and it looks like you are), you need to enter a name in the "Set species" field from the observation form. If you know the species, use that, but if not, just do the best you can, like "plant," or "weird gelatinous blob." The same applies to the observation form on the website (http://www.inaturalist.org/observations/new), but there you can also hit the "Lookup" button to see whether iNat knows about the name of the species you're using.

Also, we have a Google Group for support issues like this: http://groups.google.com/group/inaturalist