Of mosquitoes and maringouin mosquitoes and all insects of that sort, the females alone prick and suck the blood of mammifers. The males live on flowers and tree-trunks. One sees them in forest alleys and clearings, moving regularly as in army manœuvres, they are scouting, watching for females; as soon as a male has caught one he seizes her, and disappears up into the air where the union is accomplished. Only the male cricket has a noise-machine, only the female a hearing mechanism, situated in her front legs. Likewise it is the male grasshopper who sounds. A love-call? People say so, but there is no proof. Grasshoppers live, male and female in complete promiscuity lined up on the tree-bark; such a quantity of music is unnecessary, and moreover if the female grasshopper isn't deaf, she has an almost insensible hearing. It is probable that the song of insects and birds, if it is sometimes a love-call, is more often only a physiological exercise, at once necessary and disinterested. Fabre, who lived all his life among the implacable noises of the Provençal country-side, sees in "the violin of the locust, in the bag-pipe of the tree-toad, in the cymbals of the cacan only a means suitable to expressing the joy of living, the universal joy which each animal species celebrates in its own fashion."[2] Why then is the female mute? It is certainly absurd and profoundly useless to summon, in almost uninterrupted song, from morn till eve, a companion whom one sees seated beside one pumping the juice out of a plane-tree; but it has perhaps not always been so. The two sexes may have had, in the past, habits more divergent. The plane-tree which unites them in the same feeding-ground has not always grown in Provence. The unending song may have been useful at a time when the sexes lived separate, and may have remained as evidence of ancient customs. It is moreover a commonly observed fact that activities long survive the period of their utility. Man and all animals are full of maniac gestures whose movement is only explicable on the hypothesis that it had once a different intention. The female spider is nearly always superior to the male in size, industry, activity, and means of defence and attack. We will note their sexual habits later, but must observe here their particular cases of dimorphism. The Madagascar she-epeire is enormous, very handsome, black, red, silver and gold. She rigs up a formidable web in her tree, near which one sees always a modest and puerile skein, the work of a minuscule male keeping an anxious eye on the chance of sidling up to his terrible mistress, and risking his wedding-death. The argyronete or water-spider, returns the balance to the male, who is fatter, larger, and provided with longer limbs.