ANTHOZOA, 



55 



whole is drawn up, and the fragments of coral which have 

 been retained by the meshes of the net, are carefully 

 removed. 



The Mare' s-tail Coral (Isis* Hippuris). The short and stunted 

 trunks of the red coral, which in their shape resemble little oaks, 

 although composed of brittle substances, are strong enough to 

 resist the violence of the tempest ; but in the taller and more slender 

 forms, such brittleness would render them quite unfit to occupy the 

 situations in which they grow, and they would be continually liable 

 to be broken by the agitation of the sea, if, by a beautiful modifica- 

 tion in the construction of their central stem, they had not been 

 adapted to the circumstances of their position. In the Isis Hippuris, 

 therefore (Fig. 37), the central axis is constructed with alternate 



FIG. 37. isis. 



joints of stony and of ^orny substance ; so that, being thus made 

 flexible, they bend before the passing waves, and thus remain secure 

 from otherwise inevitable destruction. 



The Bark-bearing Corals (Gorgoniae)^ in their length 

 and slender form resemble osiers, or, as in the case of the 

 Gorgonia flabdlum (Fig. 38, i), are spread out into large 

 flat expansions that are called sea-fans. These zoophytes 



* Isis, a goddess ; ITTTTOS, hippos, a horse ; ovpa, oura, a tail (Mare's- 

 tail, a plant). 



t Gorgon, a mythological name. 



