uf the Wntriculicke of the Chalk. 371 



Fig. 13. The polyp-cells: vertical section highly magnified, p. 188. 



— 14. The mode of addition of fibre, p. 93. 



PI. VIII. (all in chalk except fig. 7). 

 Figs. 4 & 5. Casts showing the places of processes, p. 184. 



— 0. Polyp-cells highly magnified, p. 187. 



— 7. Root-fibre encrusted with chalcedony, p. 97. 



— 1 . Ventriculites simplex, p. 204. 



— 2 & 3. Ventriculites impressus, p. 205. 



N.B. For Ventriculites quincuncialis see PI. VII. fig. 7, & p. 207. 



PI. XIII. (all in chalk, except fig. 6, which is in flint). 

 Fig. I. Ventriculites mnricatus,]). 210. 



— 2. Ventriculites tessellatus,\t.2\\. 



— 3 &• 4. Different sections of V. tessellatus, p. 2 1 1 . 



— 5. Ventriculites cavatus, p. 212. 



— 6. Ventriculites striatus. p. 212. 



— 7. Ventriculites mammillaris, p. 213. 



N.B. For Ventriculites latiplidatus see fig. D, p. 215. 



— 8. Ventriculites decurrens, p. 215. 



— 9. Variety tenuiplicatus, p. 215. 



— 10. Ventriculites radiafus, p. 218; 



— 11. Section of V. quincuncialis, p. 208. 



— 12. Section of V. mnricatus, p. 210. 



— 13. Plaits of V. striatus, pp. 214, 216. 



— 14. Plaits of V. mammillaris, pp. 214, 216. 



— 15. Plaits of V. radiafus, p. 216. 



N.B. For Ventriculites bicomplicatus see fig. E, p. 219. 



PI. XIV. (all in chalk). 



Fig. 1. Cephalites longitudinalis, p. 281. 



— 2. Cephalites guttatus, p. 282. 



— 3. Cephalites paradoxus, p. 283. 



— 4 & 5. Outer and inner surfaces of Cephalites alternans, p. 283. 



— 6. Cephalites bullatus, p. 284. 



— 7. Section of Cephalites bullatus, p. 284. 



— 8. Cephalites retrusus (moulded from a cast in flint), p. 285. 



— 9. Cephalites catenifer, p. 286. 



— 10. Cephalites compressus, p. 287. 



— 11. Cephalites capitatus, p. 288. 



— 12. Cephalites campanulatus, p. 289. 



— 13. Vertical section of Cephalites campanulatus, p. 292. 



— 14. Piece of the matrix from inside of C. catenifer, showing projecting 



parts, which filled the depressions in the living animal, broken 

 away, p. 286. 



— 15. Transverse section of fold of membrane of C. catenifer, p. 287. 



— 16. Plaits of C catenifer, p. 2S7. 



PI. XV. (all in chalk, except, fig. 6, which is flint). 

 Fig. 1. Cephalites constrictus, p. 292. 



— 2. Cephalites perforatum, p. 294. 



— 3. Brachiolites tuberosus, p. 354. 



— 4. Brachiolites elegans, p. 355. 



— 5. Brachiolites convolutus. The specimen has been vertically divided 



and one-half cleared out, thus showing the convolutions and the 

 interior, p. 355. 

 N.B. For Brachiolites angularis see fig. O, p. 357. 



25* 



