CORALLINES. 



143 



te 



produce the effect of two op- 

 posing flights of stairs. These 

 wings are waving, vandyked, 

 and fringed on their outer 

 edge, and of a brilliant yel- 

 low ; the dentature of the 

 fringe being the lodging of 

 their pretty little . polyps, 

 which display occasionally 

 their gaping mouths and ex- 

 panded gills. The polyps 

 are white and semi-transpa- 

 rent. When they display 

 their rays, the margin of 



Fig. 62. Loose-winped 

 Virgularia, Virgularu 

 mirabilis (Lamarck). 



Fig. 63. Branch of Virgularia, 

 enlarged. 



each wing presents an edging 

 of silvery stars. 



The Umbellularia have a 

 very long stem, supported by 

 a bone (Fig. 64) of the same 

 length, and terminated at the 

 summit only by a cluster of 

 polyps. They have been 

 found in the Greenland and 

 other northern seas. 



The Veretillum, which in- 

 habit the Mediterranean (Fig. 

 65), have a simple cylindrical 

 body, without branchiae, and 



Fig. 64. Umbellularia Greculan- 

 drea (Lamarck). 



