It forms this sheet of mucous and particles drop down on the mucous. Because mucous is expensive to make, this animal actually then ingests the mucous along with the captured particles. We have Carinaria , which is another snail. Here is all its innards in here. We have the mouth up here with the eyes and intestine or the stomach goes all the way through here.
Squids are another type of mollusc - and are still gelatinous zooplankton.
You can see the beak right here. We have a few areas that are not see-through. You've things like the gut, the ink sack and the gills that you can spot but other than that, squids, mid water squids are almost completely transparent. With the exception of animals like Bruce showed you, this is Octopoteuthis which is the exception to almost every rule. This is the one I like to give to invertebrate biology students on lab practicals.