THOUGHTS 



ON 



ANIMALCULES; 



OR, A GLIMPSE OF THE 



INVISIBLE WORLD 



REVEALED BY THE MICROSCOPE. 

 BY 



GIDEON ALGERNON MANTELL, ESQ., LL.D., F.E.S., 



AUTHOR OF THE "WONDERS OF GEOLOGY," ETC. 



THE PHYSALIA PELAGICA, page 88. 



" In the leaves of every forest in the flowers of every garden in the waters 

 of every rivulet there are worlds teeming with life, and numberless as are the 

 glories of the firmament." 



DR. CHALMERS. 



LONDON: 

 JOHN MURRAY, ALBEMARLE STREET. 



1846. 



