SNAILS. 337 



behind some old tree, or against a sheltered wall, 

 fixing the openings of their shells against each 

 other, or on the substance beneath, and adhering 

 so firmly in a mass, that the thrush cannot by any 

 means draw them wholly, or singly, from their 

 asylum. In the warmer portion of the year they 

 rest separate, and adhere but slightly ; and should 

 the summer be a dry one, the bird makes ample 

 amends for the disappointment in winter, intrudes 

 its bill under the margin of the opening, detaches 

 them from their hold, and destroys them in great 

 numbers. In the summers of 1825 and 1826, 

 both hot and dry ones, necessity rendered the 

 thrush unusually assiduous in its pursuits ; and 

 every large stone in the lane, or under the old 

 hedge, was strewed with the fragments of its ban- 

 quet. This has more than once reminded me of 

 the fable of the " Four Bulls ; " united invincible, 

 when separated an easy prey ; but, with the ex- 

 ception of this season, and this bird, I know no 

 casualty to which the garden snail is exposed- 



Ignorant as we are of the scope, limitation, and 

 even existence, of certain faculties in animals, we 

 can frequently do little more than conjecture the 

 means whereby they perform many of the func- 

 tions of life. This ignorance leads us naturally at 

 times to refer these powers to the agency of senses 

 like our own; but, in most instances, probably 

 without any foundation in truth. No creature 



z 



