WILTSHIRE. — ON THE RED CHALK OF ENGLAND. 



265 



be adduced : Belemnites jacuhm ; a small crustacean, Astaciis ornatus ; 

 and a large liamite, called Hamites Beanii. 



To the south of the Red Chalk at Speeton, and adjoining it, occurs, 

 as I lately mentioned, the White Chalk. The fossils in this part are 

 not numerous ; an inoceramus, a terebratula, and rarely an ammo- 

 nite, are found. But the White Chalk higher up, that is, farther 

 south, below Flamborough Head, near Bridlington Quay, is very fossil- 

 iferous, containing corals, echini, a bed of marsupites, as well as that 

 very remarkable and extensive collection of marine forms, the silicified 

 sponges, thousands of which can be seen at low water scattered up 

 and down, and imbedded in the scars, or rocks. Tliis chalk, however, 

 has its drawbacks, for being very hard — indeed, so much so as to 

 ring under the strokes of a hammer — specimens cannot be obtained 

 without much trouble. I must make an exception with regard to the 

 sponges. They are composed of silex ; hence, long soaking in very 

 dilute hydrochloric acid will do more and better work after the 

 fossils have been brought home, than fifty chisels. The calcareous 

 matter is slowly dissolved away, and then forms come into view as 

 delicate and lovely as any that can be noted in the modern sponge 

 tribe. Most of the common kinds of the Flamborough sponges will be 

 found figured and named in Professor Phillips' Geology of Yorkshire ; 

 the rarer in the Magazine of Natural History for 1839. 



Let us now return to the village of Speeton, and endeavour to 

 follow the winding course of the Red Chalk to its visible termination, 

 some hundred miles to the south-east, in the county of Norfolk. 



By a reference to the map (page 262), where the bed is laid down, 

 it is seen that the Red Chalk adjoins the White Chalk during its 

 entire length ; that it first takes a westerly direction for about twenty 

 miles, and then suddenly turning at a &harp angle proceeds south-east 

 for the remainder of its course. 



Some persons might suppose when they see the map, that if they 

 were to travel to any of the towns or villages near the line, they 

 would of necessity be able to see the Red Chalk in situ. No such 

 thing ; the upper soil, or vegetation, or man's work, may quite con- 

 ceal all traces. It is only at natural sections like the cliffs just 

 spoken of, or by other means, such as wells, ka., that we can acquire 

 a true idea of the ground beneath us. Who, for example, that lives 



