DESCRIPTION OF FOSSILS. 



FORAMINIFERA. 



The foraminifera are an order of that class of animals known 

 as rhizopods, the name meaning root-footed. The rhizopods 

 are very minute animals, resembling, under the microscope, a 

 mass of jelly full of little bubbles. They move about by push- 

 ing out portions of this jelly-like substance into thread-like pro- 

 trusions, which may be absorbed back into the animal. This 

 is how they get the name "root-footed." Food particles are 

 taken into the body anywhere, as there is no mouth, and digested 

 and the waste portions thrown out wherever they happen to 

 be, as there are no digestive organs. The animal can best be 

 understood as a minute bit of jelly-like substance, called sar- 

 code, capable of motion and the assimilation of food. Some 

 of these rhizopods have shells with minute holes in them 

 through which the thread-like feet are protruded. These feet 

 often interlace, forming a network about the animal. These 

 animals are called foraminifera on account of the little holes in 

 the shell. They live in both fresh and saltwater, but are much 

 more numerous in the oceans, where, minute as they are, their 

 shells make up masses of deposits which become hardened 

 into limestone and extend over vast areas. 



The only foraminifera which have been made known from 

 the rocks of eastern Kansas are those often called "petrified 

 wheat." Their scientific name is Fusulina secalira, the latter 

 name meaning a rye grain. They are very numerous ; often 

 layers of limestone from two to ten feet thick, made up almost 

 entirely of these shells, extend across the state from north to 

 south. For further information, the reader is referred to Mr. 

 Mc( lung's article in Volume IV of this Survey, entitled 

 " Microscopic Organisms of the Upper Cretaceous," on page 

 415. 



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