ON CRETACEOUS POLYZOA. 393 
6. Cricopora gracilis, Goldf. 
7. Entalophora ramosissima, d’Orb. 
8. Py Francqana, d’Orb, (Clausa id. d’Orb.) 
9. 5 micropora, d’Orb. (Clausa d’Orb.) 
10. Retepora (Idmonea) clathrata, Goldf. 
11. Heteropora cryptopora (Multicrescis). 
12. Petalopora pulchella, Lonsd. (Cavea regularis, d’Orb.). 
13. Radiopora pustulosa, d’Orb. 
14. Domopora tuberculata, d’Orb. 
15. Ceriopora polymorpha, Goldf. 
16. Truncatula pinnata, Rom. 
17. Eschara Cybele, d’Orb. 
VII. Potyzoa or THE BLackpown AND Hatpon Beps. 
The Rey. W. Downes, in a paper on ‘The Zones of the Blackdown 
Beds,’! mentioned four species of Polyzoa preserved in the Bristol 
Museum. 
1. Heteropora dichotoma, Blainy. 
F 3 ceryptopora, Goldf, 
3. Ceriopora gracilis, Goldf. 
4, Radiopora bulbosa, d’Orb. 
The species 1 to 3, with others not yet catalogued, are found also in the 
Haldon beds of Devon. The Radiopora bulbosa may be picked up in large 
masses as water-worn pebbles on the Devonshire coast ; and I have a very 
fine example thus derived, which was given to me some years ago by Mr. 
Downes, but the Haldon species still await investigation. 
VIII. Potyzoa or THE Rep CHaLk or HUNSTANTON. 
It is not my intention, here or elsewhere, to enter upon any lengthy 
discussion as to the origin or the exact geological horizon of the Red 
Chalk. It will, however, be an advantage if I preface my Red Chalk list 
of Polyzoa with a few remarks on this very peculiar deposit. The 
Rey. T. Wiltshire, writing in 1859 on the Red Chalk of England,? says: 
‘This stratum... nowhere forms a mass of any great thickness or 
extent ; perhaps if thirty feet be taken as its maximum of thickness, four 
feet as its minimum, and one hundred miles as its utmost extent in length, 
the truth will be arrived at. It may be said, also, to be peculiar to 
England, for the Scaglia, or Red Chalk, of the Italians has little in com- 
mon with that of our country. The two differ widely in appearance, in 
situation, and in fossils’ (p. 261). A good sketch map showing the 
extent of the Red Chalk as it is traced in the Hast of England (from 
Hunstanton to Filey), and a fine view of Hunstanton Cliff, embellish 
' Mr. Wiltshire’s paper. Only three species of Polyzoa are mentioned by 
Mr. Wiltshire. 
1. Idmonea dilatata, d’Orb. Terr. Crét., tab. 632; Speeton. 
2. Diastopora ramosa, Dixon, Geol. Sussex, p. 295 ; Hunstanton. 
3. Ceriopora spongites, Goldf. Petrifac. p. 25, t. 10, fig. 14; Speeton. 
* Quart. Journ. Geol. Soc. Feb. 1882, pp. 75-94. 
? The Geologist, 1859, pp. 261-278. 
