Lankester—-Craq. 149 
III. On tHE Cracs or SurroLk AND ANTWERP.* (Part II.) 
By E. Ray Lanxsstsr, Esq. 
Relations of the Crags of Antwerp and Suffolk.—Having thus 
passed through the various strata, we may inquire what relation 
the three Crags bear to the Suffolk deposits. The lists of Mollusca * 
which I have carefully compiled from the researches of Mr. Searles 
Wood, on the one hand, and of M. Nyst, on the other, have been 
revised by my friend Dr. S. P. Woodward, and will enable us satis- 
factorily to determine this point. A short list of the Mollusca of 
the Antwerp Crag was published by Sir Charles Lyell in 1852, in 
his comprehensive and admirable paper on the Belgian Tertiaries ; 
but although the comparison was made with the English beds, yet, 
in the absence of any section showing the superposition of the Ant- 
werp Crags, and also on account of the imperfections in the list of 
Shells, the results then obtained cannot have so much value as those 
which have since been arrived at, and which give the proportions 
of recent and fossil forms in the five beds under consideration, 
thus :— 
In the Red Crag, 45 per cent. of the Mollusca are extinct. 
»  Coralline Crag, 50 Bs 5 
»» Upper Antwerp Crag, 47 ,, 
» Middle Antwerp Crag, 59 ,, 
» Lower Antwerp Crag, 65 ,, 
This undoubtedly shows that the Red and Coralline Crags of Suf- 
folk and the Upper Crag of Antwerp are far more closely connected 
with each other than any one of them is with the Middle or Lower 
Crag, or than these latter are with each other: and on this account 
the Red, Coralline, and Upper Antwerp Crags may be considered as 
Upper Pliocene; the Middle Antwerp Crag, as Middle Pliocene; and 
the Lower or Black Crag, as Lower Pliocene. If the total number 
of species as yet discovered in each bed be examined, it is found 
that the Red and Coralline Crags of Suffolk have the largest num- 
bers ; most probably because they have been the best searched. The 
numbers are—Red Crag 231, Coralline Crag 299, Upper Antwerp 
Crag 115, Middle Antwerp Crag 117, Lower Antwerp Crag 168. 
Until the other day, the fauna of the Black Crag appeared as scanty 
as that of the two higher Crags of Antwerp; but M. Nyst, having 
directed his researches to a deposit at Edeghem, swelled its lists in 
the same way as it is quite possible that the number of known Mol- 
lusea in the Upper and Middle Crags may be increased. 
A Table showing the results to be derived from the lists of Mol- 
lusea is added to this paper. There being two sets of figures, one 
for the extinct species, and the other for living species, it will be 
seen that there are but 9 extinct and 17 living species which run 
through all the strata; whilst there are 60 extinct and 76 living 
species common to the Red and Coralline Crags; 24 extinct and 37 
* Continued from page 106. 
~ The lists are too long for publication in this Magazine 
