Other Hydrophilidae carry their egg-cocoons about with them beneath the abdomen.
C. Janet observed that in a nest of Lasius alienus, established by a single female, the first workers emerged from their cocoons on the 102nd day.
The various agricultural products, cattle and mules, cheese, wines and spirits, silk cocoons and gypsum make up the bulk of the exports.
A large variety of materials have been used in their manufacture by different peoples at different times - painted linen and shavings of stained horn by the Egyptians, gold and silver by the Romans, rice-paper by the Chinese, silkworm cocoons in Italy, the plumage of highly coloured birds in South America, wax, small tinted shells, &c. At the beginning of the 8th century the French, who originally learnt the art from the Italians, made great advances in the accuracy of their reproductions, and towards the end of that century the Paris manufacturers enjoyed a world-wide reputation.
The decrease in the annual average production of cocoons is shown in the preceding table.