A species of the genus _Butalis_, the _Butalis_ or _Alucita granella_, is, in certain cantons of France, one of the greatest pests to agriculture. The caterpillar of the _Tinea granella_ undergoes its metamorphosis in the interior of grains of barley and of wheat, which it devours without being perceived from without. The female lays her eggs on the grains of corn before they are ripe. From four to six days after, the eggs are hatched, and the young caterpillars are hardly as thick as a hair. Each one takes possession of a grain of corn, and penetrates into it by an imperceptible opening. They eat the flower without injuring the teguments of the grain. [Illustration: Fig. 292.--Tinea granella.] When it has attained its full size it spins itself a cocoon of white silk in the interior of the grain, which, after having been its lodging and its larder, becomes for some time its tomb. It has, however, taken care beforehand to make at the extremity of the grain a circular opening, through which the moth may come out when the grains have been threshed and stored up in the granary. It is important to mention the _Tineina_, not because these little moths are beautiful--they are, on the contrary, very dingy--but because it is in this group that are found those insects which do the greatest damage to our crops. The moths of the genus _Tinea_ are very small. Their wings, which are greyish or brownish, are generally marked with whitish and yellowish spots or lines. These are the little moths which, in our houses, burn themselves so frequently in the flames of the candles. Their caterpillars are small, voracious, and deserve, on account of the damage which they cause, to be compared to rats and mice. Furnished with powerful jaws, they destroy everything they find in their way, such as woollen stuffs, hair, furs, feathers, grain, &c. The _Tineina_ are divisible into three groups: 1st, the species hurtful to our stuffs and furs; 2ndly, the species which destroy our corn crops; 3rdly, the _phytophagous_ species, that is to say, those which feed on plants. In the first subdivision must be classed the Fur Moth, the Woollen Moth, and the Hair Moth. The Woollen Moth is represented in the figure on next page. Its caterpillar has the form of a worm, and is of a glossy whiteness, with a few hairs thinly sprinkled over it and a grey line on its back. It is enclosed in a tube, or sheath, open at both ends, in the interior of which is a sort of tissue of wool, sometimes blue, sometimes green, sometimes red, according to the colour of the stuff to which the insect attaches itself and which it despoils. The exterior of this sheath is, on the contrary, formed of silk made by the insect itself, of a whitish colour.