CORALS. 411 



ro, and is found in tolerably large masses, adhering to rocks, 

 madrepores, and similar substances. All the Clavellarias are of 

 somewhat similar shape, though variable in size and color, and 

 may be recognized by several conspicuous characteristics. The 

 tubes are nearly cylindrical, but tapering, as shown in the illus- 

 tration, and forming a foot-stalk which is more or less bent. 



The texture is somewhat leathery, and is strengthened by in- 

 numerable spicules of a calcareous nature, which are agglomera- 

 ted together in bundles. These spicules are too small to be dis- 

 tinguished except by the microscope, but under a tolerably high 

 power they are seen to be long and spindle-shaped, sharp at both 

 ends, and encircled with little rounded knobs set in regular rows. 

 These tubes are always placed very closely together, but do not 

 adhere to each other, their grooved surfaces being always distinct. 



The animal by which this tube is formed is a very pretty one, 

 cylindrical, with eight radiating tentacles of a violet gray. The 

 color of the tube is green for the upper half, and then changes to 

 brown, so that the contrast of the two colors is very decided. 

 The average length of the tube is two inches. 



There are several other species of Clavellaria, among which 

 may be noticed the Violet Clavellaria {Clavellaria violacea). 

 This is a much smaller species, but is colored in a more bold and 

 decided manner. In this creature the tubes are dark violet and 

 the tentacles are bright yellow. They do not, however, project 

 from the tube as boldly as those of the preceding species, but only 

 just show their tips above the entrance, withdrawing them smart- 

 ly on the least alarm. As they retreat they slightly contract the 

 orifice, their bodies being fastened to the inside of the tube. 



Toward the centre of the illustration, and on the right-hand 

 side, may be seen a remarkable tree-like object,- covered with 

 long, tendril-like appendages, each tipped with a radiating beard. 

 This zoophyte is known by the title of Xenia elongala, and, on 

 account of its singular form, is a very conspicuous species. 



Examples of this genus are spread over many of the hotter 

 parts of the world, some being found in the Bed Sea, and all no- 

 table for the remarkable form of the animal and its submarine 

 home. The present species has been chosen more for the singu- 

 larity of its form than the beauty of its colors, which can not be 

 expressed in the simple black and white of a wood-cut. Some 

 species of this genus have the star-like tentacles colored with 



