ON THE GENUS ALVEOLITES ETC. 369 



Roemeri, Bill., from the Devonian) which agree entirely with 

 Alveolites, as generally understood, both in form and in the 

 possession of a few irregular mural pores, but which differ 

 from A. suborlicularis and its allies in possessing no traces 

 whatever of septal ridges. In most characters these forms agree 

 entirely with A. Fo-ugti, E. & H., which has already been 

 removed by Lindstrom to the genus Favosites. This would 

 perhaps be the best course to pursue, provisionally at any rate, 

 with forms such as A. Goldfussi, Bill. ; but this would necessitate 

 a further enlargement of the characters assigned to Favosites, since 

 the corals in question differ both from the typical Favosites and 

 from the aberrant F. {Alveolites) Fougti, in possessing few and 

 remote mural pores. Further investigation will therefore be re- 

 quired before a final conclusion on this point can be arrived at. 



DESCRIPTION OF PLATES XIX. & XX. 



Fig. 1. A vertical section of the polished surface of a portion of Chcetetes {Alveo- 

 lites) sepiosus, Flam., from the "Vaults" Limestone, Lower Carboni- 

 ferous group, Dunbar. Drawn from a specimen in the collection of 

 the Geological Survey of Scotland (Edinburgh). Of natural size. 



2. A portion of a horizontal section of the same specimen. At a is shown 



a portion of the matrix in which it was imbedded. Also of nat. size. 



3. A small portion of the surface of fig. 2, considerably enlarged, showing 



the transverse sections of the corallites. 



4. Applies to an outline of a flask-shaped specimen of the preceding coral, 



ChcBtetes {Alveolites) septosus, Flem. This was obtained from the 

 Lower Carboniferous or Calciferous Sandstone series, Blackwood 

 Ridge, New Quarry, Ecclefechan, Dumfriesshire. From the collection 

 of the Geological Survey of Scotland (Edinb.). Outline reduced less 

 than ^ nat. size. 



5. The appearance of th weathered surface of the preceding, of nat. size. 



6. Part of the same area as fig. 5, but considerably enlarged. 



7. A partially longitudinal and somewhat obliquely fractured section of 



Chatetes ? radians, Fischer. From the Carboniferous Limestone, 

 Hardendale, Nab, Shap, Westmoreland. Of nat. size, from a specimen 

 in the cabinet of Prof. Nicholson. 



8. A small portion of the weathered surface of the preceding specimen. 



9. A horizontal section of the preceding as viewed under the microscope, 



and magnified about 6 diameters, 



10. A vertical section of the same, also enlarged 6 diameters. 



11. A portion of the exposed and slightly weathered surface of a mass of 



Ckmtetes hyperhoretis, Nicholson and Etheridge. From the Lower 

 Carboniferous Limestone group, Charleston, Fife. Drawn of nat. 

 size from a specimen in the cabinet of Prof. Nicholson. 



31* 



