A humble Weevil will do what the bird dares not undertake and will do it better. She will entrust her eggs to the white tufts; she will destroy the seed of the ferocious plant, which, were it not subjected to a severe thinning, would become an agricultural calamity.
At the beginning of July I cut off a well-flowered thistle-top; I dip the stem in a bottle full of water and cover my repellent bouquet with a wire-gauze cover, after stocking it with a dozen Weevils. The pairing takes place. Soon the mothers dive down among the flowers and seed-plumes.
A fortnight later, each head is feeding one to four larvæ, already far advanced. Things go fast with the Larini: all must be finished before the thistle-heads wither. September is not over by the time that the insect has assumed the adult form; but there are still laggards at this period, represented by nymphs and even by larvæ.
Built on the same plane as the Artichoke-weevil’s, the dwelling consists of a sheath having [[56]]for its base a basin hollowed in the surface of the receptacle. In either case the architecture is the same; so is the method of work. A quilt of hairs, borrowed from the seed-plumes and the mane-like fringe of the receptacle, is heaped around the grub and cemented with the lacquer of the intestine.
Outside this downy bed of wadding is spread a further mattress, a layer of granular excrement. The artist has not thought fit to employ its digestive refuse to greater advantage. It has something better at its disposal. Like the other Larini, it is able to turn the sordid sewer into a valuable glue- and varnish-factory.
Will this lodging, so softly padded, be its winter home? Not so. In January I inspect the old thistle-heads; in none of them do I find the Weevil. The autumnal population has migrated. For this I see a very good reason.
The thistle, now dead and bare, an ash-grey ruin, is still standing, is still holding out against the north-wind, thanks to its strength and the firmness of its roots; but its flower-heads, emptied by age, are wide open, exposing their contents to the inclemencies of the weather. The fleece of the receptacle is a sponge that swells up with the rain and tenaciously retains the moisture. The same may be said of the cardoon and the artichoke.
In either case we no longer find the fortress of the carlina, encompassed with convergent folioles; what we see is a spacious, roofless ruin, abandoned [[57]]to the damp and the cold. The white tuft of the ferocious thistle and the blue tuft of the artichoke are delightful villas in summer; in winter they are uninhabitable residences, sweating mildew. Prudence, the safeguard of the humble, counsels the owners to forestall the final dilapidation and to move. The advice is accepted. At the approach of the rains and frosts, both Larini leave the home of their birth and proceed to take up their winter-quarters elsewhere: precisely where I do not know. [[58]]