Spittlebugs feed from the xylem rather than the phloem in plants. The xylem contains large amounts of water. Rather than exude this extra as honeydew, they spew this over themselves. It’s an amazing feat of nature that nymphs don’t drown when the hatch, but as with everything in nature, there is a fascinating design to meet this need. The nymphs have an air-filled tube-like canal on their underside of their body; this tube can be extended out of the spittle, like a snorkel!