440 University of Kansas Geological Survey. 



Artliropoda. 



This division comprises those animals which possess a seg- 

 mented body and jointed appendages which are variable in num- 

 ber. The body and the appendages are usually protected by 

 an external covering or skeleton. This subkingdom comprises 

 four great classes: (1) Crustacea. (2) Arachnida. (3) 

 Myriapoda. (4) Insecta. Among the representatives of these 

 classes are the crabs, crayfish, lobsters, spiders, centipedes, and 

 insects. The Crustaceans are the only representatives of this 

 subkingdom found in the Kansas Cretaceous beds. This class 

 is represented by two genera and at least twice as many species. 



