SEA-FAN MAKERS. 1 95 



spicules are being constantly consolidated into the 

 tube, and the tube thus increases in height. In some 

 cases I have been able to trace the mesenteric bands, 

 which attach the lower portion of the body of the 

 polyp to the walls of the skeleton tube, as far as the 

 second external septum in depth ; and it is very 

 evident that, as the outer walls of the tube become 

 consolidated, not only does the tube become elon- 

 gated, but the polyp elevates itself at the same time 

 in the tube." l 



As the " Organ-pipe coral" is an inhabitant of wa'rm 

 latitudes, and has seldom been observed or studied, 

 even there, in the living state, the foregoing particu- 

 lars of its animals will have a special interest. This 

 is one of the objects with which so many are familiar, 

 in its dead condition, or when nothing remains save 

 the skeleton, but concerning the inhabitants of which 

 so little was previously known that even now it may 

 be assumed that information is far from complete. 

 Indeed, its reproduction and development, which 

 would entail observation over a considerable period 

 of time, is still guessed at rather than demonstrated. 

 From analogy it may be assumed that in these 

 particulars it does not differ greatly from its imme- 



1 " On the Animal of the Organ-pipe Coral," by Prof. 

 E. Perceval Wright, in " Annals of Natural History," vol. iii. 

 (1869) p. 377. 



O 2 



