Mrs. Thynne and Mr. Gosse on the Increase of Madrepores. 453 



lo a laughing friend that it is quite well, notwithstanding its 

 singular appearance. 



14. October 5th. — The mouth is so distended, that a four- 

 penny piece might be laid inside it. Indeed, the creature would 

 have taken the form of a ring, were it not for the skin or in- 

 tegument which is the lower part of the animal covering the 

 surface of the rock. It appears also as though it were going to 

 tear itself asunder into four unequal portions ; and the white 

 convoluted threads, or vermiform filaments, of which they have 

 such an abundance, lie on the base beyond the edge of the mouth 

 (see PI. XVII. fig. 1). I suppose it must really be dying; or 

 can it be a form of spontaneous fission ? 



15. October 6th. — The little creature is now nearly torn 

 asunder. In one part it is only united by an attenuated thread, 

 which the least movement of the water would break. On this 

 thread are the tips of two tentacula (fig. 2). 



16. October 7th. — The thread is quite broken, and the two 

 ends which it united have curled round to meet those parts 

 which are dividing on the right and left. Part of the base is 

 rent, and the opposite division is much narrower (fig. 3). 



17. October 9th. — The base is rent in two, and the division 

 at the top is quite broken. The two ends have turned round to 

 meet those parts which are breaking on the right and left. 

 These four parts stand opposite each other — a large one and a 

 small one at present slightly united (figs. 4 and 5). 



18. October 12th. — The pair on the right have quite sepa- 

 rated, and the ends of each portion have become united by a 

 new membrane, which was at first dii'ty white, but is now be- 

 ginning to assume the beautiful bright apricot-colour of the 

 other part of the little creature. The pair on the left are not 

 yet quite asunder. They have the appearance of four distinct 

 Madrepores, though not of the same size. Each one takes food 

 that is presented to it, though the mouth is at present entirely 

 on one side, part of it being formed of the new membrane (figs. 

 6 and 7). 



19. October 25th. — The mouth is becoming more in the 

 centre; tips of new tentacula are developing on the new mem- 

 brane, and also many more between the old tentacula (fig. 8). 



The second Madrepore is passing through the same process 

 of spontaneous fission. 



20. December 16th. — The mouth of the Madrepores is now 

 about half-way towards the centre. They have removed more 

 than an inch from each other. The smallest Madrepore, after 

 its subdivision, Oct. 12th, contained sixteen old tentacula, as I 

 have drawn it (fig. 7) ; at the present date it has eighty-five. 



21. March 22nd, 1851 . — Tomorrow I leave Tenby for London; 



