386 ARTICULATED ANIMALS. 
promptitude to infinity. The remains of such 
minute animals have added much more to the 
mass of materials which compose the exterior 
crust of the globe, than the bones of Elephants, 
Hippopotami, and Whales. 
Chapter XVI. 
Proofs of Design in the Structure of Fossil 
Articulated Animals. 
The third grand division in Cuvier's arrange- 
ment of the animal kingdom, viz. the articulated 
animals, comprehends four classes. 
1. The Annelidans, or worms v/ith red blood. 
2. Crustaceans, most familiar to us under the 
form of Crabs and Lobsters. 
3. Arachnidans, or Spiders. 
4. Insects. 
SECTION I. 
First Class of Articulated Animals. 
FOSSIL ANNELIDANS. 
However numerous may have been the ancient 
species of Annelidans without a shelly covering, 
naked worms of this class can have left but sliaht 
