The agreement of these strata with certain portions of the Yorkshire series is very striking and remarkable. The bed 2 is shown, by its petrological characters, its stratigraphical relations, and its characteristic fossil to be the " Hunstanton Red-rock."
The Tock (3) is very fossiliferous. The following is a list of the species which have been recorded from it, excluding the doubtful ones (founded on the small fragments of Ancyloceras, which are very numerous here *).
Belemnites jaculum, Phil.
— lateralis, Phil.
Ammonites speetonensis, Y. 3f B.
— — , var. venustus, Phil.
— — , var. concinnus, Phil.
— Nisus, D' Orb.
— rotula, Sow.
Ancyloceras (Crioceras) Duvali, Lev.
Ancyloceras (Crioceras) Emmerici, Lev.
— (Crioceras) Puzosianus, D' Orb.
— (Hamites) raricostatus, Phil.
Thracia Phillipsi, Rom.
Pholas constricta, Phil.
Serpula Phillipsi, Rom.
Rhynchonella nuciformis, Sow. sp. ?
Fish-remains.
On a comparison of this list with that given in my paper on the Speeton Clay†, it will be found that of the fourteen forms twelve occur in our "zone of Ammonites speetonensis" some of them being highly characteristic of that zone. Serpula Phillipsi occurs in the beds immediately above those with Am. speetonensis at Speeton ; but in my personal searches (on which alone the lists are based) I did not succeed in finding it lower down in the series ; in Germany, however, this fossil certainly ranges downward to the bottom of the Neocomian. Concerning the fossil called Terebratula nuciformis, Sow., by Prof. Wiebel, I feel much doubt, but would suggest that it may not improbably be the Rhynchonella Renauxiana of D'Orbigny.
From the conclusive evidence just adduced, there cannot, therefore, be any doubt that in the little island of Heligoland (a mere speck in the German Ocean) we have, preserved in a very remarkable manner amid the general destruction of the strata of this area, most interesting vestiges of the " Hunstanton Red-rock," and of the "zone of Ammonites speetonensis" of the Yorkshire series. The relation of these in the island of Heligoland is precisely the same as in the pit above described at West Heslerton. Heligoland is situated 325 miles due east of Speeton, and 150 miles from the nearest exposure of the Neocomian beds on the Continent.
2. Holland. — Although this country is now almost completely covered with drift and alluvial deposits, I found in the great Museum of Natural History at Leyden, interesting evidences of the former wide extension of the Neocomian strata. Among the large collections of boulders in that museum are a number composed of a peculiar yellow limestone, precisely similar to that of Tealby, and in some cases enclosing specimens of the highly characteristic Pecten cinctus. Boulders of the same material are not rare in the
- Vide Fr. Ad. Romer, Verst. nordd. Kreidegeb. (1841). Wiebel, Die Insel
Helgoland (Hamburg, 1848).
† Quart. Journ. Geol. Soc. vol. xxiv. p. 235.
