Dr. Lindstrom on Operculated Corals. 125 



plete, being only composed of valves of two long and narrow sclerites, 

 which do not close the mouth of the calice. Frimn. lepadifera and 

 the Calyptrophora, on the contrary, have a complete operculum, and 

 they agree in several points with Goniophyllum. The valves in all 

 these are triangular, and cover completely the top of the polypary, 

 in such a way that some valves repose with their borders on those 

 of the others. As is the case in GoniopJiyllum the median line of 

 the outside of the valves is deepened, and to this channel or groove 

 an elevated ridge corresponds on the interior surface. This ridge 

 in the Primnose is a fulcrum to muscles from the basis of the tenta- 

 cula. In other respects there is not much similarity between the 

 Palaeozoic and the recent species. The opercular valves of the 

 Primnose have ^own in a radial way, the calcareous bodies radiat- 

 ing towards all sides from a nucleus, or centrum, situated at the 

 lower side of the operculum. In the Eugosa, again, the growth has 

 been concentric, each new layer being added around the previous. 

 Moreover, no traces of spiculge or calcareous bodies are seen, the oper- 

 culum and the coral are made up of homogeneous matter, and there is 

 no reason to believe that the original structure has been obliterated 

 by external metamorphosing agencies. Other fossils, Brachiopoda 

 and Perforate Corals, in the same stratum, retain the most minute 

 details of their characteristic microscopical structure unaltered, and 

 metamorphosing agencies affect generally all fossils in the same 

 stratum. The opercular valves of the Primnose are, in all proba- 

 bility, morphologically identical with the scales that cover the polyp 

 all round, to which they bear a close resemblance, being entirely 

 composed of the same sort of calcareous bodies, arranged in the same 

 radial manner. If this scaly covering of the polyp is an ectoder- 

 mic secretion, the calcareous spiculee that are scattered so abundantly 

 in the interior of the soft parts of the animal, and which are quite 

 dissimilar to the spiculse {" KalTchdrper," Koelliker) that compose 

 the scales and the opercular valves, alone represent in the Primnoae 

 the sclerenchyma or the polyparium proper of other Anthozoa. I 

 think there exists some sort of homology to these ectodermic scales 

 of the Primnoae amongst the Eugosa in Cyatliophylhmi {Pholido- 

 phylhim, n.g.), Loveni Edw. and H.^ Specimens of this very common 

 and widely distributed fossil show, when in a good state of preserva- 

 tion, a thick covering of small {^^^), very thin scales, tightly 

 clustered together in longitudinal rows along the costge. There are 

 two rows of scales on each costa, this being indeed double or divided 



1 The authors of this species themselves doubt its belonging to the genus Cyatbo- 

 phyllum (Hist. Nat. Cor. III., p. 367, Brit. Foss. Corals, p. 280, pi. 66, fig. 2). In 

 this they are quite right, as it does not in any way coincide with the species commonly 

 considered as Cyathophylla. Its strange exothecal covering in scaly rows, its septa, 

 its well-developed tabulae, its double costae, and the complete want of dissepimental 

 structure between the septa, justify my forming a new genus out of it, which I propose 

 to name PhoUdophyllum. As it now stands, it contains only a single species, Fh. 

 Loveni, which is found most abundantly in Gotland, and also in Kussia (Oesel), 

 Norway (Christiania), England (Dudley and other localities), N. America (Lake 

 Huron, St. Joseph's Island). It occurs also in the Drift of Northern Germany, 

 from whence Ludwig, in Palaeontographica, vol. xiv., pi. 47, fig. 3, and pi. 51, fig. 4, 

 has obtained it and named it Tceniocyathus and Tceniolepas spinosa. 



