54 FORAMINIFERA 



the foraminifera of the past, or the time 

 required for the deposition of such vast 

 hosts of shells in the formation of limestone 

 rocks. 



The creatures have left behind the most 

 gigantic results ; results, too, that are on the 

 side of the elevating operations of Nature as 

 opposed to the degrading or wearing-down 

 influences, such as the action of water, 

 oxygen, or carbonic acid, &c. 



Other members of the foraminifera, known 

 as fusulina and rotalia, took a large share in 

 building up the limestones of the Old World. 



Notwithstanding the minuteness of these 

 shells, most of them are partitioned into 

 several chambers, even if sufficiently small to 

 drop through the eye of a needle. 



Plancus counted 6,000 shells in an ounce of 

 sand from the Adriatic. Omitting the sand 

 and weighing the shells only, 280,000 would 

 be required to weigh a single ounce. 



One of the best examples of a strand com- 

 posed almost entirely of foraminiferal shells 

 in the British Islands is that of Dog's Bay on 



