130 PEOF. P. M. DUNCAN ON THE STEDCTURE AND 



has no alliance with Turhinoseris and Palceoseris, nobis, as Mr. Tomes 

 supposes. 



The next commnnication to which I have to direct attention is 

 " On the Fossil Madreporaria of the Great Oolite of the counties of 

 Gloucester and Oxford," by E. F. Tomes, Esq., P.G.S., Quart. Journ. 

 Geol. Soc. vol. xxxix. 1883, p. 168. This communication contains 

 some very interesting and valuable stratigraphical data, and speaks 

 well for the author's industry. He assigns the species often to 

 definite horizons, and adds several very interesting forms to the 

 fauna. But there are criticisms of the work of previous observers 

 in it, and especially of Milne-Edwards and Jules Haime and myself, 

 which require answering. 



The confusion into which Mr. Tomes has thrown the group of 

 species which Milne-Edwards and Jules Haime placed within the 

 genus Cyathophora of Michelin, is added to by his giving new generic 

 diagnoses to this genus and to Oryptocoenia *. He first of all states 

 that the genera Cyathophora and Oryptocoenia are of d'Orbigny's 

 proposition, forgetting that the first was not d'Orbigny's, and that 

 it was chosen from Michelin's work by Milne-Edwards and Jules 

 Haime to supersede Oryptocoenia of d'Orbigny, the definition of 

 which was not sufficiently exact to be worth anything. Next, very 

 properly, seeing the impossibility of retaining the two genera ac- 

 cording to De Eromentel's classification, he says, the genera, " in my 

 opinion, require some modification," which he gives as follows {op. 

 cit. p. 194) : — " OyathopJiora. Coenenchyma small in quantity and 

 dense. Gemmation proceeding from it in close proximity to the walls 

 of the corallites, if not actually from the walls themselves. Septa 

 feebly developed, and the cycles not traceable. Calicos generally 

 much crowded, appearing at many heights, often oblique, oval, or 

 even polygonal." Now this is not a modification, for it is a diagnosis 

 totally unlike that of Michelin. Not a word is said about the tabulse 

 which were noticed by Milne-Edwards ; but it is to be inferred that 

 they are recognized, for the genus is separated in the classification 

 from Oryptocoenia by Mr. Tomes, and is placed in the family Theco- 

 stegitse of De From., and amongst the Tabulata. Then, on the next 

 page, we read, " It is with very great doubt that I have given this 

 species (Oyathophora Bourgueti) a place in the Zoantharia Tabulata, 

 not having, by any means, satisfied myself as to its real affinities." 

 Yet this species is the only one of the genus, according to Mr. Tomes, 

 which is in the British Oolitic fauna. 



* Cryptoccenia was thus diagnosed by d'Orbigny : — 



" A Tremaccenia without a styliform columella." 



C. hacciformis was the type. There was great doubt whether the form was 

 not a true Stylina the columella of which had fallen out by wear and weather. 



Tremaccenia was dropped and it is now Stylina. 



The diagnosis of CryptoccRnia was insufficient, and Milne-Edwards and Jules 

 Haime, finding a remarkable arrangement of the endotheca in certain corals 

 which otherwise would have been considered to be Stylincs without columellas, 

 associated the species with the genus Oyathophora of Michelin. 



The imperfect tabulae of Oyathophora fill up the visceral cavity to a considerable 

 extent, and it is evident that the columella is wanting in the types. 



