348 LUCERNARIAD.E. 



(?) POCILLOrORA INTERSTINCTA (Muller). 



At a meeting of the Royal Society of Edinburgh (Trans. 

 March, 1846), Dr. Fleming exhibited a characteristic draw- 

 ing of a Pocillapora presumed to be of this species, which 

 was obtained by Dr. Hibbert in the Shetland Seas. Dr. 

 Fleming had expected that a detailed description of this 

 would have been published before the appearance of his 

 " History of British Animals," in 1828. It is, however, I 

 believe, still a desideratum. 



The genus is marked by the following characters : 

 Corallum massive or sub-tree-like, with thick, imperforate 

 walls. Visceral chambers divided by well-developed hori- 

 zontal partitions, or floors, in successive stages. Plates 

 rudimentary. Galices shallow, with a thick ring at the 

 bottom of each, forming a sort of columella. 



LUCERNAKIADiE. 



Contrary to my original intention, I have determined to 

 exclude this family from my work. Their true affinities 

 are with the Hydrozoa and Medusa?. The gelatinous tex- 

 ture, the expanded umbrella, the ovaries in the substance 

 of the umbrella, the four-lipped mouth placed at the end of 

 a free peduncle,* and the quadripartite arrangement, are all 

 Medusan characters. The tentacles in marginal groups are 

 found in Bougainvillcea, and their form, — knobs at the tip 

 of long footstalks, — agrees more with Slabberia than with 

 Corynactis and Caryophyllia. 



9 See my fig. of Campamdaria, in Devonsh. Coast, p. 296, pi. xviii. 



