234 ZOOPHYTES. 



modated to the curvatures of the shell, which may contribute to the secu- 

 rity of its adhesion. 



The body of the Actinia maculata is yellowish, of various intensity, 

 according to the specimen, speckled with vivid purple. The tentacula are 

 very numerous, proportionally small and slender, arranged in a triple row, 

 and the exterior of the root surrounded by a narrow purple ring. 



On the slightest shock, long slender filaments, either white or purple, 

 according to the specimen, issue through obscure low papillae on the sur- 

 face of the skin. 



The aspect of this Actinia is much affected by its position. If its 

 nature be to invest a convex surface, one which is flat may be less con- 

 genial. Thus the specimen, Plate XLVIII. fig. 3, which is seen there as 

 seated on the shell of a hermit crab, having detached itself, diffused the 

 base on the bottom of a glass vessel, not unlike the wings of a butterfly, 

 fig. 4. But until the animal adheres, the basis remains a long time with 

 its whole under surface merely folded together. 



Specimens feed readily on such substances as Actinias usually receive. 

 All are very greedy of worms. 



Thousands of minute opaque bright-yellow spherules are produced by 

 these animals in July, August, September, and October. Several hundreds, 

 or greater numbers, appear at once ; and the same Actinia has produced 

 them repeatedly. But, spite of careful preservation, nothing satisfactory 

 resulted, fig. 5. 



All the colours of this Actinia, one of the most beautiful and picturesque 

 of the tribe, are revived, and become much more vivid on renewal of water 

 recent from the sea. 



Naturalists speak of a horny membrane, or expansion of the skin, over 

 the shell, to which the Actinia affixes itself; but this seems to be only its 

 own skin, which may be thickened or consolidated under some circum- 

 stances, by a certain secretion from the body. I have not seen it other- 

 wise than quite flexible and fragile. 



I have been indebted to Sir Walter C. Trevelyan, Baronet, for some 

 fine specimens from the Island of Arran. 



