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ZOOLOGY. 



which have been produced by gemmation (Lat. gemma, a 

 bud), or budding from a single individual. These colonies 

 are provided with a chitinous or calcareous integument. 



FIG. 50. FLUSTRA. 



The Flustra may be readily found covering the large 

 fronds of the Laminarian sea- weed with a lace-like crust. 

 Other species are spread over shells or submerged stones. 

 Others look like diminutive shrubs, and are merely attached 



