HILL; GEOLOGY OF JAMAICA. 239 



crov.'ii surrouiidmg the columellar termination. The upper end of the columella 

 is in a depression surrounded above by the crown. These swollen ends of the 

 septa sometimes fuse laterally with one another. The sides of the septa are beset 

 with crowded pointed granules. Endothecal dissepiments very abundant ; in 

 the cross section of one interseptal loculus seven were counted ; usually at least 

 three are present in each cross section of the loculi. The dissepiments are thin. 



Locality. Craigie, Parish of Hanover. 



Type. Collection of Institute of Jamaica, Kingston, Jamaica. 



DIPLORIA, Edwards and Haime. 



In examining the literature on Diploria I find that certain of its features are 

 so vaguely described that one is likely to fail to recognize the genus. In 

 characterizing the genus Edwards and Haime state, " la columelle est spon- 

 gieuse, essentielle et bien developpee." ^ Duncan's description of the columella 

 in his "Ee vision of the Families and Genera of the Madreporaria,"^ is merely 

 a translation of the original French. In examining specimens of the species of 

 Diploria herein described, of D. crassolamellosa, Edwards and Haime, and from 

 figures of D. Jlexuosissima, d'Achiardi, the persistent presence of a lamellar 

 columella was noticed. 



In the first characterization of Diploria,^ o\\\j the Mceandrina cerehriformis 

 of Lamarck is mentioned, so this species, the common Diploria cerehriformis of 

 the West Indies, is the type of the genus. A study of this species has shown 

 that it possesses a lamellar columella, which is given a spongy appearance in 

 places by the inner termini of some septa fusing to it and sending out some 

 processes in the axial space. The columella is not continuous throughout the 

 whole length of a series, but is broken here and there by what probably are 

 calicinal centres. A section of one series parallel to the septal planes showed a 

 perfectly distinct lamellar columella through a vertical distance of I cm. 

 This was the length of the section. 



The usual definition of Diploria must be modified so as to include the obser- 

 vations above noted. 



Diploria conferticostata, sp. nov. 



Plate XXXIX. Figs. 1-3. 



1365. Diploria crassolamellosa, Duncan (non Edwards and Haime) Quart. Jour. 



Geol. Soc. London, Vol. XXI. pp. 7, 12. 

 1868. Diploria crassolamellosa, Duncan, Quart. Jour. Geol. Soc. London, Vol. XXIV. 



p. 24. 



1 Hist. Naturelle des Coralliaires, 1857, Tom. IL p. 401. 



2 Journ. of the Linn. Soc (Zo51.), 1884, Vol. XVIIL p. 88. 



8 Comptes Rendus de I'Acad. des Sc. (Paris), 1848, Tom. XXVIL p. 493. 



