G. GALAXAURA. 115 



proach some species of Tubularias, as much as they do 

 the Corallinas ; like the first, their stem and branches 

 are fistular and of a cylindrical form, frequently mark- 

 ed with parallel and circular rings ; like the second, 

 they are articulated, regularly ramified, and of a mem- 

 brano-fibrous substance, incrusted with a calcareous 

 matter which effervesces in acids. But again these 

 Polypidoms have not that rigidity which seems pe- 

 culiar to the Corallinas ; they approach nearer the 

 Liagoras in their flaccidity, their substance, and the 

 position of their polypi. These animalcula are 

 placed at the extremities of the ramifications, 

 which frequently appear closed by the drying of 

 the body of the animal, which is formed of a non-cre- 

 taceous substance, more homy and more gelatinous 

 than the other parts of the Polypidom : sometimes 

 the substance is the same throughout the whole sur- 

 face ; at others, the ramifications are open at their 

 extremities. With such variety of character, we 

 cannot wonder at the difficulty of determining their 

 order. 



The form, however, of the Galaxauras does not 

 greatly vary ; they are most of them dichotomous and 

 regular in their divisions. Some of them are strongly 

 articulated, and in others the articulations are 

 scarcely discernible ; these last have in general their 

 rings more strongly marked than the first; it appears 

 as if nature had provided them with these rings to 

 supply the deficiency of articulations. 



The colours of the species that are preserved in 

 collections show a diversity of hues, from the violet 

 to green, yellow, or white, sometimes most pleasingly 



