Title reads: "British International Pictures Limited presents Secrets of Nature. Distributed by Wardour Films Ltd. The Froth Blower. Produced by British Instructional Films Ltd."
Cuckoo spit clinging to plants. Voice over explains that this froth has nothing to do with the cuckoo but with a small insect called a froghopper. C/U of a froghopper on a stem - the film follows its life history. Tweezers are used to pull grasses apart to show where the froghopper lays its eggs. The eggs are covered with a hard coating - we are shown a C/U of a row of eggs. Froghopper nymph climbs up plant after hatching then it finds an angle in the plant to "blow bubbles to make a home". Sap is drawn from the stem of the plant then blown out again as bubbles. The froghopper covers itself with bubbles. Extreme close up of the lancet of froghopper compared to a needle. Stem of a plant is pierced with a needle to show the white sap. The froghopper lancet pierces the stem, the creature sucks in sap and transfers it to bubble blower. Froghopper feeds on the sap and makes more bubbles to repair its home when needed. It leaves cuckoo-spit when it is ready to change from a nymph to a froghopper. It sheds its skin - shown with time lapse photography. Its wings slowly expand. Its power to jump has developed. Cuckoo-spit shown on foxgloves, the froghopper that chooses this plant is different. This type of froghopper changes inside the bubbles rather than on the stem of the plant. A froghopper is fished out of his bubble home with a twig. We see this type of froghopper changing inside his bubbles.
Note: this film was revised with the co-operation of the National Committee for Visual Aids in Education and called "Cuckoo-Spit" - see other record. This version may have more images not found in the other version. Three prints exist - check for best quality.