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ZOOLOGY 



Lingula, an 

 ancient 

 type still 

 surviving 



to convey small particles of food to the mouth. These 

 structures are fully developed in the typical lampshells, 

 but are variously modified in other families. The sexes 

 in the Brachiopoda are separate. 



The burrowing species, typified by Lingula, are oblong 

 and flattened, with thin shells, and have a long, worm- 

 like pedicel. Living specimens may be obtained on the 

 California and southern Atlantic coasts, and extremely 

 similar shells come from the older Palaeozoic rocks. We 

 thus think of the Lingula as one of the oldest of all 

 living creatures, little changed during many millions of 

 years. 



