THE CONQUEST OF THE DRY LAND 195 



squirts out from mouth-papillae tiny jets of 

 slime, and it is believed to do this also as a 

 means of catching small insects. Peripatus is 

 of great interest to naturalists, because in some 

 important respects it resembles a worm, while, 

 in others, especially in the possession of breath- 

 ing tubes, it has risen to a higher level, and 

 shows relationship with insects. It must be very 

 well adapted to its mode of life, for it is very 

 widespread in warm countries, being found, 



FIG. 20. A CENTIPEDE. 



with slight differences between the species, in 

 Central America, the West Indies, in Chili, in 

 New Zealand and Australia, in Asia, in Cen- 

 tral Africa, and at the Cape of Good Hope. 

 The second great invasion led on to centi- 

 pedes, millipedes, insects, and spiders, and 

 just as the worm-invasion resulted in the 

 making of fertile soil, so the second invasion 

 had for its great consequence the establishing 

 of a linkage between flowering plants and the 



