I have no doubt that if you have a garden and if there are some shrubs in that garden then you will have seen these frothy, foaming clusters of bubbles on them in the mornings in late spring and early summer. We commonly know them as cuckoo-spit as they start to appear not long after the cuckoo returns to our shores and starts to sing.
This phenomenon has nothing to do with the cuckoo of course, they are the work of the females of a tiny spittle bug we know as the common froghopper (Philaenus spumarius). Each drop of foaming fluid contains the eggs of the bug which will remain within it until it has dried out which takes about ten days. Whilst in the foam it is protected from predators and can live safely in an environment where the temperature and humidity are perfectly controlled.
The insect itself is tiny, mainly nocturnal and is rarely seen. It can run and fly but its most effective form of self defence against predation is an amazing ability to suddenly jump (or hop) a considerable distance in relation to its size - hence froghopper! The origins of the Latin name, Philaenus spumarius, are explained by Wikipedia; Philaenus comes from the Greek philein meaning love so I guess this is a love bug! Spumaris comes the latin spuma meaning sparkling and, of course, refers to its foam nest.