The air-bubble chamber can be small and fit just the spider's abdomen (shown here) with its legs and thorax hanging out, or it can enclose the entire animal.
A diving bell spider, Argyroneta aquatica, shown here on underwater vegetation.
A diving bell spider has snagged a water flea and is consuming the prey inside the air-bubble chamber.
A female diving bell spider maintains her egg coccoon within the air chamber she has created within a silken web.
Here, a female diving bell spider has her egg cocoon enclosed within the air bubble attached to her silk web. When the eggs hatch, the little ones will immediately form their own air chambers.
Diving bell spiders, like this one, create their chamber by collecting a large air bubble from the surface, which they bring underwater and attach to a silk web connected to pond vegetation.