Mrs. Thynne and Mr. Gosse on the Increase of Madrepores. 455 



perfect young one, which, when expanded, is nearly the size of a 

 small pea, and has fifteen tentacula ; it is attached to the lower 

 membrane of the mother Madrepore, which is turned up (PI. XVII. 

 fig. 11)*. The Madrepores seldom adhere so closely to the rock, 

 and with such a fine, firm edge, as the Actiniae do. Sometimes 

 the young one withdraws into the parent, and then a darkish 

 spot is all that is visible. 



26. July 1st. — I find two other gemmules, one on a perfect 

 specimen, the other on an imperfect one. 



27. July 6th. — A perfect specimen has again divided — this 

 time into two parts. Two of the imperfect ones have also now 

 divided, as they should have done earlier. 



28. July 12th. — Another gemma on a perfect specimen. 



29. July 15th. — A perfect specimen, on which is a gemma, 

 has subdivided into two. The gemma expanded itself most 

 happily during the process, and seemed quite unconscious of 

 ^jny disturbance. All the gemm£e grow from the lowest [basal] 

 ynembrane of the Madrepore, the same as the first I described 

 [§25]. 



30. July 27th. — Another perfect specimen, on which is also 

 a gemmule, has divided into three parts. It appeared to make 

 a most decided effort to separate into four. I thought the one 

 mentioned July 6th did so : this time, three is the result. In 

 their natural state, the motion of the water must assist the 

 fission. 



31. August 6th. — Since my last date, the imperfect specimen, 

 on which was a gemmule, and another perfect specimen, on 

 which was also a gemmule, have both divided into three por- 

 tions, the gemmules, as before, evincing no consciousness of the 

 occurrence. 



32. August 10th. — One of the portions of the perfect speci- 

 men which I described as dividing into two parts (July 6th) has 

 again separated into two ; and the last of my imperfect ones has 

 subdivided since my last date. The gemmules assist in finding 

 food for themselves — at least I judge so from the occasionally 

 rapid contraction of the tentacula ; and they take mussel with 

 much avidity if I give it them. I think they also share the 

 sustenance provided by the mother, as when I feed her, they 

 dilate themselves afterwards in the same manner. 



33. August 15th. — I see in three of the gemmules a little 

 knot of vermiform filaments ; but they are large in proportion ^ 

 to the little animal, so that I cannot decide whether they belong 

 to the parent or the young one. The outer covering of the 

 young ones is so very transparent, that I can see any opake 

 object within them. . . . 



* Apparently the base reverted at its edge. — P. H. G. 



