134 CfARYOPHYLLLE. PART m. 



pellucid filaments or ribbons, full of thread-cells, lying" 

 in coils within the chambers which surround the sto- 

 mach. 



We are indebted to Mrs. Thynne's interesting obser- 

 vations on the Caryophyllia Smithii in her aquarium 

 for the life -history of the animals armed with this for- 

 midable artillery. This madrepore, which inhabits many 

 parts of the European seas, at various depths, is a species 

 of the only lainelliform genus of corals which range 

 beyond the tropics. It is a solitary individual polype, 

 with an external calcareous cylindrical coat, wider at 

 the base, when it is fixed to a rock; and the mouth, 

 which has several rows of tentacles, is in the centre of the 

 disk of the cylinder. The tentacles are delicate, trans- 

 parent, granular tubes, about an inch long, tapering to 

 their extremities, and ending in an opaque white knob 

 full of chambered thread-cells with their darts ; but the 

 thread-cells are of a larger size in the ribbons coiled in 

 the chambers round the stomach of the animal. These 

 madrepores are described by Mrs. Thynne as of various 

 tints, from a pure white to a bright apricot colour. At 

 intervals they eject from the mouth a whitish blue fluid, 

 resembling wood smoke, in a stream three or four inches 

 long, sometimes containing a few eggs. But the eggs, 

 though no doubt formed at the base of the lamellse, be- 

 come densely packed like fine dust in the hollows of the 

 tentacles, from whence they are expelled by contractions, 

 and escape by the mouth. The eggs lie quiet for a few 

 days in the place where they are deposited : by and by 

 they begin to rotate, slowly at first, then more rapidly, 

 and finally they are developed into most minute madre- 

 pores, with the star and colour of the parent. In a few 

 months they become as large as a crown piece, with a 

 very wide mouth and a membranous integument or 

 covering, for they do not get their hard calcareous coat 

 till they are two years old. While in that soft state 

 they propagate by spontaneous division, which always 



