THE CRETACEOUS SYSTEM. 



735 



curve or bow, having one end at Flamborough Head, and the other on the Humber, 

 the middle part bending inland. The breadth of the extremities of the bow, both 

 at the ocean and the river, is comparatively small; but that of the central region 

 amounts to about 15 miles, and the length from end to end to about sixty, without 

 including the sinuosities of the outline. The chalk first appears on the coast, above the 

 level of the sea, a little to the north of Bridlington Quay. From thence it gradually 

 rises towards Flamborough and Speeton, forming the cliffs, which rise precipitously 300 

 feet, but reaching a greater elevation away from the shore. Proceeding westward 

 towards the wolds, the chalk becomes still more lofty, and attains its highest elevation in 

 Wilton beacon, ascertained to be 809 feet above the level of the sea. From thence, 

 towards the Humber, the hills diminish ; yet at Hunsley beacon, six miles from the river, 

 the elevation is still 531 feet. The most striking part of the district is the Flamborough 

 headland, and its neighbourhood. The chalk here shows a tendency to split in a perpen- 

 dicular direction, and the cliffs in consequence exhibit in various places somewhat of a 

 columnar aspect. The rough waves of the ocean beating into the lower part of the per- 

 pendicular fissures have hollowed out niches, grottoes, and large caves, some of them 

 highly romantic, harder or more protected masses of chalk remaining as pillars to support 

 the undermined rock. In the loftier Speeton cliffs, a few miles further on the coast, an 

 analogous effect appears at their summit, produced by the beating of the rains, to that 

 caused by the dashing of the waves at the base of those at Flamborough. Deep sinuosi- 

 ties and breaks have been worn by the rains in the upper part of these rocks, the firmer 

 chalk remaining between them, presenting to a spectator from the beach the appearance 

 of the walls of some stupendous castle, surmounted by a range of pinnacles. A less 

 boisterous sea, and a sloping mound, keep the base comparatively uninjured. The 

 Speeton cliffs are interesting, for here the lower coloured chalk is exposed beneath the 

 upper, the former exhibiting a brick-red or chocolate colour, with green, blue, and grey 

 tinges, which strikingly contrast with the milk-white aspect of the latter, brilliant when 

 lighted up by the beams of the rising or the setting sun. 



The fossils of the chalk, and of the cretaceous system in general, are eminently the 

 remains of oceanic life, very few examples of land organisms occurring in any of its 

 formations. Plants are rare, and are nearly all referable to marine types, fuci, and other 

 sea-weeds, a circumstance which is understood as indicating that the sea was very little 

 disturbed by inundations from the land during the deposition of the strata, otherwise 

 the remains of ferns and other forms of terrestrial vegetation would have been im- 

 bedded. Among the spoils of the ocean we are presented 

 with sponges, zoophytes, star-fishes, many shells, and echi- 

 ni tes. Of the latter, a most abundant family, the specimen is 

 common Spatangus cor-anguinum, or the heart-shaped 

 echinite, which appears in profile and with a view of the 

 summit. Remains of vertebrated fishes have been exhumed by 

 Dr. Mantell, but no mammalia have been discovered. " There 

 appears," says Professor Phillips, " no sufficient evidence in 

 the fossils of this system to justify any positive inference as to 

 the character of the climate then prevailing in the northern 



Spatangus cor-anguinum. ZOnCS." 



An addition to the cretaceous system, its uppermost member, entirely wanting in the 

 British series, occurs on the continent, remarkable for bringing to light a marine reptile, 

 the remains of which have since been found in the chalk of England. This is a friable, 

 shelly, and sandy limestone, containing layers of flints, of which St. Peter's Mountain, 

 in the neighbourhood of Maestricht, is composed. Here the celebrated Hoffman, in the 



