262 



Marvels of the Universe 



behind the head, where they are covered by a flap with loose edges and l<no\vn appropriately as the 

 mantle. On the right margin of this mantle is an opening to the gill-chamber, where the slug's 

 blood is purified. Within the substance of the mantle are a few grains of shelly matter that, in a 

 poor way, represent the spiral shell of the snail. From this stoutest part of the body the common 

 sorts of slugs taper away to the rear. 



In the Worm-eating Slug much of this is reversed. The stoutest part of the slug is right behind, 

 and it tapers forwards to the very slender head. We were once told by a friend who had discovered 

 one of these slugs in his garden that he had witnessed the extraordinary sight of a slug gliding 

 backwards He was an observant man, or he would never have taken note of the fact that slugs 

 ordinarily go with the thickest part forward ; but not sufficiently observant, or he would have 



noticed that this remarkable slug had a rather 

 prominent shell. The Worm-eating Slug wears 

 quite a small mantle covering its air-chamber, 

 which is situated at the extreme hind-end of 

 the body, and this mantle is almost covered by 

 the small, thick shell. An ordinary slug has its 

 mouth armed with jaws for cutting the stalks of 

 the juicy seedlings, and a wonderful ribbon- 

 shaped tongue studded with flinty hooks for 

 rasping the said seedlings into pulp. The 

 Worm-eating Slug has lips, but no jaws. It 

 has a long ribbon-shaped tongue like other 

 slugs, but the hooks upon it are barbed. 



These differences arc all beautifully related 

 to the peculiar habits of the Worm-eating Slug. 

 Its great mission in life is to restrict the undue 

 multiplication of the beneficent earthworm. Its 

 small head and tapering body, capable of ex- 

 tension to a length of three inches or more, 

 enable it to enter the earthworms' burrows like 

 a ferret in a rabbit's run. In so doing its body 

 fills the space, so its air-chamber must be at the 

 extremity of its body to be provided with air. 

 Now these slugs not only consume worms and 

 subterranean beetle-grubs, but are not above 

 making a meal off their own kindred. If one 

 of them were followed by another in the same 

 boring, the second one might begin to eat the first ; so to guard against accidents of this kind 

 each wears over his air-chamber the hard little shell which is proof against the tongue-hooks of 

 his kindred. A portion of this wonderful tongue-ribbon, much enlarged, is here shown. Throughout 

 its length it bears about fifty rows of the curved and barbed teeth, and in each row there are 

 fifty-one teeth. The ribbon is partly thrust out, the hooks are pressed into the worm's flesh, and 

 he is dragged into the slug's gullet. 



THE SLUG'S TEETH. 



A portion of the tongue or tooth-ribbon < 



[./. /''. Conper. 



if the Wor 



Slug. Tfiere are fifty rows of teetK, 

 fifty-one teeth. 



and 



n-eating 

 sists of 



THE TRAVELLER'S TREE 



Everything that has life is in one way or another a marvel ; but we are too apt to consider as such 

 only those things that are huge or ugly, or to which sentiment has given a fancy name. The 

 Traveller's Tree is a case in point. A palm-like plant, somewhat nearl}? allied to the banana and 



