PEOPLING OF LAND AND SEA 171 



It was otherwise with the immigration responsible for the 

 Insects, whose role, in our days, is so important. For them a 

 new conquest was in store — the conquest of the air. Until their 

 appearance the only living organisms that had mounted up 

 into the air were the spores of Cryptogamous plants, the pollen 

 grains of Conifers, and perhaps the cysts of the Infusorians, 

 all borne along by the wind, and they were nothing but dust. 

 At first the only living organisms creeping about in the moss 

 were peculiar creatures like Acantherpestes, Palceocampa, and 

 Euphorberia. These creatures had some of the characters of 

 Peripatus, but were more varied in form and often carried dorsal 

 appendages, some of which have been interpreted as branchiae. 

 Doubtless they were the sole prey that the primitive Scorpions 

 could secure. The Myriapods themselves, although rapid in 

 their course, adhered strictly to the surfaces over which they 

 ran, and contributed a very slight modification to the 

 manifestations of life. With the appearance of the Insects a 

 great change takes place. All over the world creatures with 

 elongated limbs and very vivacious movements, begin to 

 multiply. New locomotor organs, their wings, carry them into 

 the air, and with a single flight they cover notable distances. 

 Before their coming, scarcely any sounds could have been 

 heard on earth but the whistling of the wind, the rustling of 

 branches stirred in its passage, the fall of the cones from the 

 trees, above which must often have arisen the roar of the 

 tempest, and of rivers in spate, the booming of the waves 

 whipped into fury, the crash of thunder, the explosions of 

 volcanoes, or the subterranean rumblings heralding earth- 

 quakes. Then came the first humming of rapidly beating 

 wings, and the strident voices of Cicadas, Grasshoppers, and 

 Crickets, great and small, singing, on the threshold of the dark 

 forests, the feast of the sun. The Insects in their countless 

 hordes carried everywhere a new animation. They swarmed 

 on the plants, devouring their leaves, boring into the bark, 

 draining the sap, sipping the nectar from the flowers, and 

 causing the appearance of bizarre swellings and galls on the 

 surface of stems and leaves where they had pierced them ; 

 but also fertilizing the flowers and manufacturing wax, honey, 

 and silk ; and, if they sometimes became troublesome pests, 

 like the Flies, or active propagators of disease, like all those 

 Insects which stab in order to draw blood, they became on 



