PLATE XVIII. 



All the figure* in this Plate are from specimens from Lummaton in my Colled ion 



except when otherwise stated. 



Crania proavia, Goldfuss? (Page 160.) 

 Fig. 

 1. A small specimen, imperfect above, attached to the hinge of a specimen of 

 P. hrevirostris, X 7. 1 a, side view. 



Polypora populata, n. sp. (Page 174.) 



2. A large specimen, partly a natural section and partly retaining the poriferous 



internal surface. 2 a, one fenestrule, X 10. Lummaton ? Torquay 

 Museum. 



3. Another specimen, showing the external surface. 



4. Another specimen, X 10, showing the external surface. 



Polypora pagan a, n. sp. (Page 176.) 



5. A small specimen, chiefly a section, but retaining the inner surface on the 

 upper part. 5 a, a fenestrule, X 10. 



Fenestella panata, n. sp. (Page 165.) 



6. Specimen of inner surface. 



7. Another specimen, showing the ribbed external face, X 10. 



8. A similar specimen with rather larger fenestrules, X 10. Lummaton. 



Woodwardian Museum. 



9. Specimen of the internal face, showing an additional line of pores in one 



branch just before divarication, X 10. 

 L0. Another specimen, showing a peculiar mode of multiplication of branches 

 which is occasionally seen, X 10. 



