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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jail. 22, 



transverse and in some places complicated laminae seem to him to 

 bear the characters of true diaphragms, and to be seated within the 

 visceral cavities ; whereas the concave or transverse laminae in M. 

 Michelin's delineations of Stylince* are without the cavities. M. 

 M. -Edwards and M. Haime give moreover the following as one of 

 the generic characters : " Polypierites tres allonges, unis entre eux 

 au moyen d'un grand developpement des cotes et de Pexothequef ." 

 The internal composition of the visceral receptacles is, unfortunately, 

 not shown in the figures before quoted ; but if rightly understood, they 

 are traversed vertically by lamellae (" cloisons," MM. Edwards and 

 Haime), the broadest of which touch the columella J, while no men- 

 tion is made of diaphragms. On the contrary, M. Michelin says, the 

 lamellae composing the terminal star in Cyathophora Richardi, 

 " couvrant a peine la moitie de la superficie de la derniere cloison" 

 (diaphragm) ; and no allusion is made to a columella §. M. M. -Ed- 

 wards and M. Haime acknowledge fully the difficulties which they 

 encountered in determining the species of Stylince described by them ; 

 and it is impossible to doubt, that the evidence to which they had 

 access was thoroughly considered before they concluded that Cyatho- 

 phora differs not from true Stylina\\. The author of the present 

 notice wishes only to maintain that he was justified in drawing the 

 inference which he did from the data before him, while to have gone 

 beyond them would have rightly made him amenable to censure ; and 

 he conceives that he would have erred, if, during his search for infor- 

 mation, he had considered the fossils (Styh Gaulardi or echinulata 

 and S, tubulata) delineated by M. Michelin in pi. 21. figs 5 and 6, to 

 be generically allied to the coral {Cya. Richardi) represented in pi. 26. 

 figs, la, \b. 



In the description of Cyathophora? elegans 9 ^ allusion is made to the 

 Astrea alveolata of Goldfuss**; and that fossil is included, as well 

 as Cya. Richardi, among the synonyms to Stylina Bourguetiff, with 

 the remark, " nous parait etre un echantillon dont les chambres se 

 seraient remplies apres la disparition des cloisons et de la columelle." 

 By the kindness of Mr. Wilson, of Lydstip House, near Tenby, the 

 author has been able to examine a named specimen of Astrea alveo- 

 lata. It agreed perfectly with Goldfuss's fig. 3 a, but the specimen, 

 though fine, being silicified, had the subordinate structures much ob- 

 scured by the concretions due to mineralization. No doubt, however, 

 could be entertained that the visceral cavities were crossed more or 

 less horizontally by diaphragms — that a central axis had never existed 

 — and that the lamellae extended only to a limited distance, the most 

 projecting in the best-preserved examples being six in number — 

 Goldfuss says six or eight. The nature of the specimen prevented 

 the detailed structure of the lamellae from being fully ascertained ; 

 but they clearly ranged from one cavity to the next, as represented in 



* Loc. cit. t Op. cit. p. 287. 



X Ann. Sc. Nat. Styl. echinulata, p. 289. 



§ Icon. Zoophy. p. 104. || Pal. Soc. vol. for 1850, p. 7L 



\ Quart. Journ. Geol. Soc. vol. v. p. 77 ? 1. 21 et seq. 

 ** Petref. p. 65. tab. 22. fig. 3a, 3*. tf Ann. Sc. Nat. p. 2 9 0-29 L 



