THE EUDENDRUM. 757 



no such power resides in these organs. The stem is of a rather soft consistency, 

 strengthened by a bony centre, which reaches nearly to its tip. 



Close to the Sea-pen may be seen an object of somewhat similar form, but con- 

 siderably elongated, and with the pinnae proportionately shorter. This is the SEA-RUSH, 

 an animal belonging to a genus that can easily be distinguished from the preceding 

 by several peculiarities. The -pinna? are short, deeply scooped above, and, with their 

 bases, partly surround the central stem. The polypes are set only upon the edges of 

 the pinnae. There is an allied species belonging to the same family, called by the 

 name of Pavonaria. In this remarkable genus, the general shape of the lengthened 

 mass is four-sided, and the polypes are arranged in a somewhat spiral form on the 

 stem, but only one side of its latter half. In our own seas, the Sea-rushes do not grow 

 to any great length ; but under a tropical sun they reach great dimensions, some of 

 them measuring more than a yard in length. 



THE last figure represents a very curious inhabitant of our seas, which is in the 

 habit of encrusting all kinds of marine bodies, such as shells, stones, and stems of 

 the large algae. Its general mass runs out into lobes, and is of a soft spongy 

 consistence, pierced v/ith little holes, from which the polypes make their appearance 

 when in health. When closely examined, the little holes or pores are seen to be formed 

 of eight rays, in a kind of star-like pattern, and corresponding to the tentacles of the 

 polypes which inhabit them. These little cells are placed at the ends of canals, which 

 permeate the whole mass, and serve to unite into one common body the vast number 

 of polypes which are thus aggregated together. When examined by the microscope, the 

 substance of the polypidon is found to be filled with tiny particles of chalky matter, 

 which serve to give consistency to the fabric, and add to its elasticity. 



WE now arrive at the Hydroida, which are known by the internal cavity being sim- 

 ple, and the creature increasing by buds thrown out from the sides. 



The left-hand figure represents an example of the family Tubulariadae, in which the 

 buds grow from the base of the tentacles, and break off their attachment as soon as 

 they have attained maturity. The buds, or young, are naked. The animals are some- 

 times naked, but are often inclosed in a horny, tubular covering, which we will term 

 the polypidon. The first family is represented by its typical genus. The polypidon 

 of this genus does not throw out branches, and the tentacles are delicate, thread-like, 

 and arranged in two circles. The germs, or buds, are set on very short footstalks, and 

 are gathered upon the bases of the lower tentacles. This being is represented of the 

 natural size. 



Before leaving this interesting family of zoophytes, we must pause awhile, to cast a 

 cursory glance at one or two of the more prominent British examples. 



The CLUB-ZOOPHYTE (Clara multicornis) has a large and rounded extremity, some- 

 thing like the head of a bludgeon, upon which are placed irregularly a number of 

 thread-like tentacles. 



The various species belonging to the genus Coryne are also worthy of notice. These 

 conspicuous, though minute zoophytes are found on our own shores, and may be 

 recognized by the globular tips of the tentacles. Sometimes the creatures are naked, 

 and sometimes they are inclosed in a rude sort of tube. The word " Coryne " is Greek, 

 and signifies a club. The head of each tentacle is most elaborately constructed, and 

 adorned with very minute tentacles, each being furnished with a small bristle at its 

 tip. These tentacles can be moved with tolerable rapidity, and are held in various at- 

 titudes, sometimes stretching out at right angles from the stem, but often bending up- 

 wards, with their heads directed towards a common centre, and have been happily com- 

 pared to the bars of a turnstile or the weighted arms of a screw press. 



Another genus is that which is appropriately named Eudendrium, from two Greek 

 words, signifying a beautiful tree. As may be presumed from its name, it has a decidedly 

 tree-like form, each twig terminating in a polype whose flower-like tentacles add in no 

 slight degree to its beauty. It is found that, when in captivity, the Eudendrium is sadly 



