ALCYONIDvE. 217 



swam freely in the water which distended the polyp, as figured by 

 Ellis. Their motions in the polyps, though circumscribed, were so in- 

 cessant, that, by watching attentively, I could observe them with the 

 naked eye ; and they became more conspicuous as the ova advanced to 

 the open base of the stomach. From their restlessness, as they ap- 

 proached the last passage which separates them from the sea, they 

 seemed to feel the impulse of a new element, which they were im- 

 patient to enjoy ; and by following the direction of that impulse, they 

 appeared to find their way into the lower extremity of the stomach, 

 without any organic arrangement to lead them into that narrow canal. 

 In their passage through the stomach, which was effected very slowly, 

 the spontaneous motions of the ova were arrested, unless some imper- 

 ceptible action of their cilia, or some contraction of their surface, 

 might tend to irritate the sides of that canal, and thus direct or hasten 

 their escape." 



Alcyoniwn, gelatinosum. Attached to old stones and shells is this 

 jelly-like transparent spongy zoophyte, growing to a height of nearly 

 a foot, and sometimes much longer. It is branched, and of a brown 

 or yellow colour, dotted with polyps, which are attached to the cells. 

 Through angular openings they protrude their arms or feelers. Dr. 

 Farre states, " The tentacula are sixteen in number (occasionally fifteen), 

 fully two-thirds the length of the body of the animal, and extremely 

 slender and flexible. When expanded they are frequently seen to roll 

 up closely upon themselves, even down to their base; the revolution 

 taking place either inwardly or outwardly, and in one or more arms at 

 the same time. Their full expansion affords a more perfect cam- 

 panulate form than is usually met with in this class, each of the arms 

 having a slight curve outwards towards its extremity, which gives to 

 the whole a very elegant appearance. It is remarkable that in some 

 specimens the arms are much shorter on one side of the body than on 

 the other." 



The last specimen we notice, belonging to this family, is the 

 handsome Tubipora musica, or Organ-pipe Coral, fig. 10, Plate V. 

 This coral is composed of parallel tubes, united by lateral plates, 

 or transverse partitions, placed at regular distances ; in this manner 

 large masses, consisting of a congeries of pipes or tubes, are formed. 

 When the animals are alive, each tube contains a polyp of a beautiful 

 bright-green colour, and the upper part of the surface is covered with 

 a gelatinous mass, formed by the confluence of the polyps. This species 

 occurs in great abundance on the coasts of New South Wales, of the 

 Red Sea, and of the Molucca Islands, varying in colour from a bright 



