44 PKOCEEDINGS OF THE GEOLOGICAL SOCIETY. [NoV. 9, 



24, DiTEtJPA DEFOEMis, Lamarck. 



This is a well-knowii species in the Upper Cretaceous rocks of 

 Normandy and Belginm, and as it has been unnoticed up to the 

 present time by English collectors, I am induced to give its syno- 

 nymy, with references to published figures. 



1815. Dentalium fZe/brme, Lamk, Animaux sans Vert. vol. v. p. 344, no. 6. 

 1825. septangular e, Flemiug, Edinburgh Phil. Journ. p. 240, pi. 12. 



f. 9. 

 1839. Serpula septemsulcata, Geinitz, Charac. der Schicht. p. 66, pi. 22. f. 6. 



1847. sulcataria, D'Archiac, Fossiles du Tourtia, p. 30, pi. 14. f.ll. 



1848. ? clavata, Kner, Kreidem. von Lemberg, pi. 5. f. 13. 



1850. Ditrwpa deformis, De RycHiolt, apud Lamarck, Melanges Pal^- 



ontologiques, p. 123. 

 1850. Dentalmm ? difforme, Sov7. in Dixon's Geol. Sussex, pi. 29. f. 10. 



EXPLAIN ATION OF PLATES III.-V.. 



niustrative of the Fossils of the Irish Cretaceous Strata. 



Plate III. 



Fig. 1. Ammonites occlusus, nat. size: a, side view with septal suture; b, back' 



view. 

 Fig. 2. Helicoceras Hibernicum : a, fragment with septal suture. 

 Fig. 3. Scaphites elegans, nat. size. 

 Fig. 4. Cinulia catenata : a, enlarged 2 diameters ; b, portion of shell, magnified ; 



c, sectional view of shell. 

 Fig. 5. Vlicatula deltoidea, nat. size : a, upper valve ; b, lower Valve. 

 Fig. 6. Scalaria alba-cretce, nat. size. 

 Fig. 7. Tun-itella unicarinata, nat. size ; upper portion representing the moidd, 



with a mesial band. 

 Fig. 8. Calyptraa Gray ana, enlarged 2 diameters : a, view from above ; b, side 



view. 



Plate IV. 



Fig. 1. Fholadomya cordata, nat. size smallest specimen: a, side view; b, front 



aspect. 



Fig. 2. Stewarti, nat. size. 



Fig. 3. obliquissima, nat. size. 



Fig. 4. Terebratidina Befrancei : a dorsal valve, nat. size. (This figure I'epre- 



sents the specimen turned half round.) 

 Fig. 5. Pecten glauconeus, enlarged 2 diameters. 

 Fig. 6. Cardium gibbosmn, enlarged 2 "diameters. 



Plate V. 



Fig. 1. Terebratida abrvpta, nat. size: a, seen from above; b, side view. 



Fig. 2. HhyncJionella limbata, var. robusta, nat. size : a, viewed from the front ; 



b, side view ; c, seen from above. 

 Fig. 3. Terebratida ( Waldheimia) Hibernica : a, b, enlarged 2 diameters ; c, a 



fragment of the beak, enlarged. 

 Fig. 4. Etheridgia mirabilis, nat. size : a, side view ; b, under surface, showing 



the radiciform processes. 

 Fig. 5. Cceloscyphia sidcata, nat. size. 

 Fig. 6. Cmloptychhim furcaticm, reduced one-half. 

 Fig. 7. Belfastiense, nat. size. 



