CHAP. XII.
NORFOLK AND SUFFOLK TERTIARIES.
209
We are indebted to Mr. Searles Wood, F.G.S., for an admirable monograph on the fossil shells of these British pliocene formations. He has not himself given us an analysis of the results of his treatise, but the following tables have been drawn up for me by Mr. S. P. Woodward, the well-known author of the 'Manual of the Mollusca, Recent and Fossil' (London, 1853–6), in order to illustrate some of the general conclusions to which Mr. Wood's careful examination of 442 species of mollusca has led.
Number of known Species of Marine Testacea in the three English Pliocene Deposits, called the Norwich, the Red, and the Coralline Crags.
Brachiopoda ................................................................................................................................................................................................................................................................................................................................................................................................ | 6 |
Conchifera ................................................................................................................................................................................................................................................................................................................................................................................................ | 206 |
Gasteropoda ................................................................................................................................................................................................................................................................................................................................................................................................ | 230 |
Total ................................................................................................................................................................................................................................................................................................................................................................................................ | 42 |
Distribution of the above Marine Testacea.
Norwich Crag81 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Red Crag225 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Coralline Crag327 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
Norwich and Red Crag (not in Cor. )33 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Norwich and Coralline (not in Red)4 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Red and Coralline (not in Norwich)116 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Norwich, Red, and Coralline19[1] ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
Proportion of Recent to Extinct Species.
Norwich Crag69 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Red Crag130 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Coralline Crag168 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
12 ................................................................................................................................................................................................................................................................................................................................................................................................ |
95 ................................................................................................................................................................................................................................................................................................................................................................................................ |
159 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
85 ................................................................................................................................................................................................................................................................................................................................................................................................ |
57 ................................................................................................................................................................................................................................................................................................................................................................................................ |
51 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
Recent Species not living now in British Seas.
Norwich Crag12 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Red Crag8 ................................................................................................................................................................................................................................................................................................................................................................................................ |
Coralline Crag2 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
0 ................................................................................................................................................................................................................................................................................................................................................................................................ |
16 ................................................................................................................................................................................................................................................................................................................................................................................................ |
27 ................................................................................................................................................................................................................................................................................................................................................................................................ |
|
- ↑ These 19 species must be added to the numbers 33, 4, and 116 respectively in order to obtain the full amount of common species in each of those cases.