52 FORAMINIFERA 



Their shells range from the simple single 

 cell or chamber to compound or multilocular 

 aggregations of considerable complexity and 

 great attractiveness of form. 



In some instances the cells are arranged 

 end to end in a straight line ; in others the 

 row of cells is arranged spirally. 



In some instances two rows of cells are 

 arranged in alternate spirals. Some have the 

 cells opposing each other around an imaginary 

 axis. There are discoidal shells of intricate 

 and complicated forms, such as the Orbitolites. 

 There are others that in their early days 

 are arranged spirally like small ammonites, 

 but which, when fully grown, have their 

 shells produced at a tangent, so that they 

 look like so many old-fashioned pistols in 

 miniature. 



The surfaces of these tiny shells show 

 numerous openings or foraminae (hence the 

 name), which are the outer orifices of 

 tubules passing through the walls of the 

 shells. 



Most of the buildings in Paris are con- 



