f) C R. M. Brydone — Stages of the Upjjer Chalk. 



Carina. — There is another pecnliaritj^ which can often be noticed 

 in either species. In transverse sections little ja<?o;ed projections 

 may be visible along the edges of the septa (see PI. Ill, Fig. 9). In 

 a vertical section cut parallel to, but not quite touching, the face of 

 the septa these projections are seen to be spines, which are arranged 

 in linear series parallel to the free edges of the septa (PI. Ill, Fig. 8). 

 They are, in fact, carma, such as are common enough in Devonian 

 corals. The appearance of this phenomenon in Carboniferous times 

 is somewhat of a myster}', for these structures do not seem to occur 

 in Touriiaisian specimens of Cyathaxonia, while they are often met 

 with in strata of "Visean age. Curiously enough, the only other 

 Carboniferous coral where this feature seems to liave been noticed 

 (a new species of Cdmpophyllum ^) also comes from Visean beds. 

 Septal projections in Cyathaxonia were first recorded by Dr. A. 

 Vauglian.- He considered that they might be the remnants of tabulae 

 subsequently destroyed, a not unnatural view in the absence of 

 vertical sections to demonstrate their true nature. As previously 

 mentioned, carinae have been observed in both C. cornu and C rushiana. 

 They are not traceable in examples of C. cornu from Tournai, and 

 cannot be considei'ed of diagnostic value in either species. 



EXPLANATION OF PLATE III. 



Photographed from camera lucida drawings (except Figs. 1, la, and 2). 

 Fig. Figs. 1-2, Lopliophyllum tortuosum (Mich.). 



1. Profile view. Nat. size. Cornet Quarry, Tournai. 

 la. Calyx of above specimen. Nat. size. 



Ih-e. Serial transverse sections from above specimen. Nat. size. 

 If. Vertical section from middle portion of above. Nat. size. 



2. Another specimen. Side view with part of calyx broken away, showing 



the cokimella. Nat. size. 



i. Lophophi/Uuni sp. {Koninckophylhnii auctt.). Vertical section, x jj. 

 Petershill Quarry, Bathgate. 



Figs. 4-7, Cyathaxonia cornu, Mich. 



4. Central part of transverse section, x 8. Southford Quarry, Dunfermline. 



5. Part of median vertical section down septa and columella, x 8. 



Southford Quarry, Dunfermline. 



6. Vertical section, showing the tabulae, x 2. Cornet Quarry, Tournai. 



7. Transverse section, x 2. Cornet Quarry, Tournai. 



8. Vertical section, showing tabulas and carinse. x 5. Stock, near Bracewell. 



9. Transverse section from above, showing carinse. x 5. 



10. Cyathaxonia rushiana, Vaugban. Central part of transverse section, 

 x 8. Bradbourne, Derbyshire. 



II. — The pkoposed Recognition of Two Stages in the Upper Chai.k. 

 By E. M. Brydone, F.G.S. 



IN the Geological Magazine for July and August last Mr. A. J. 

 Jukes-Browne made a proposal for the recognition in England, 

 France, and Germany of a boundary -line between two corresponding 



' Lee & Carruthers, loc. cit., p. 150, pi. i, figs. 3-6. 



■ "The Carboniferous Succession at Loughshinny " : Q.J.G.S., vol. Ixiv, 

 p. 460, 1908. 



