92 BOOK OP NATURE LAID OPEN. 



powers ; and the slender Worm draws and pushes 

 himself forward by his rings and contortions. The 

 wisdom in these contrivances must be immediately 

 apparent, when we consider that some of the former 

 have their habitations assigned them in the most im- 

 penetrable thickets, where an elevated stature would 

 expose them to many inconveniences. Some take 

 up their abode in the swampv banks of great rivers, 

 or among the reeds in morasses, where the weight 

 of their body, supported by legs, must have sunk 

 them deeper in the mire ; others wind their way 

 among heaps of rubbish or crumbling ruins, where 

 projecting appendages, of any description, would 

 have been apt to retard their progress ; and the naked 

 and defenceless bodies of the latter are admirably 

 adapted to those subterraneous passages which they 

 form to themselves unseen in the bowels of the earth. 



Snails, also, are a species of Reptiles; but, being 

 encumbered in their movements with their shelly 

 appendage, they are furnished with an instrument 

 peculiar to themselves, in that long, broad surface, by 

 which they pull themselves along ; and by which* 

 assisted by the glutinous substance they emit from 

 their bodies, they aiv enabled to adhere, in any po- 

 sition, to the smoothest of surfaces. 



The motion of Caterpillars in their vermicular 

 state is curiously performed, by means of a number 

 of little legs, the foremost of which are differently 

 constructed from the hindmost, but all are formed 

 in the v most suitable manner for assisting in their 

 progress on the leaves of plants. 



