- 



l"ig$. 4 & 5. Outer and inner surfaces of Cephalites alternans, p. 75. 



- 6. Cephalites bullatus, p. 76. 



- 7. Section' of Cephalites bulletins, p. 76. 



- 8. Cephalites retrusits (moulded from a cast in flint), p. 77. 



9. Cephalites catenifer, p. 78. 



10. Cephalites compressus, p. 80. 



11. Cephalites capitatits, p. 81. 



12. Cephalites campanulatus, p. 82. 



- 13. Vertical section of Cephalites campanulatus, p. 84. 



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



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

 away, p. 79. 



15. Transverse section of fold of membrane of C. catenifer, p. 79. 



16. Plaits of C. catenifer, p. 79. 



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

 Fig. 1. Cephalites constrictus, p. 84. 



2. Cephalites perforates, p. 86. 



3. Brachiolites tuber osus, p. 89. 



4. Brachiolites elegans, p. 90. 



5. Brachiolites convolulus. The specimen has been vertically divided 



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

 interior, p. 90. 

 N.B. For Brachiolites angularis see fig. O, p. 92. 



6. Brachiolites racemosus : the right-hand portion shows the form of the 



arms as seen on outside of flint; the left-hand portion shows the 

 root and longitudinal sections of several arms, p. 99. 



7. Brachiolites tubulatus, p. 101. 



PI. XVI. (all in chalk). 



Fig. 1. Brachiolites foliaceus : the lower part showing the outside, the upper 



part a vertical section, p. 99. 

 - 2. Brachiolites digitatus, p. 100. 



3. Brachiolites fenestratus, p. 102. 



4. Brachiolites labrosus, p. 103. 



5. Brachiolites protentus, p. 104. 



ERRATUM. 



At page 17, line 16, a reference is made to PI. VII. by mistake for 

 PI. VIII. 



