110 GEOLOGY OF THE ISLE OF WIGHT. 



found to present the inner surface of the pericarp 

 or shell of the Chara, the nut or kernel being 

 absent. By a little practice, some of these fossils 

 may be obtained with the external surface ex- 

 posed, and, rarely, with the nut in the shell, as in 

 fig. 1, which is copied from Mr. Lyell's paper in 

 the Geolog. Trans. In the limestone at White- 

 cliff Bay, a species was discovered by Mr. Lyell, 

 having the pericarp composed of nine spiral valves, 

 covered with tubercles (fig. 2). On a recent visit 

 to that locality, there were many blocks of limestone 

 on the sea-shore, in which these bodies were so 

 numerous as to constitute a large proportion of 

 the mass, but I did not succeed in obtaining any 

 specimens with the nut ; the cavity of the pericarp 

 was generally lined with calcareous spar. In some 

 of the sands gyrogonites occur in abundance, 

 and may be detected by examining with a lens 

 a little of the earth spread out on a sheet of 

 paper. 



Fossil Shells. — The shells at Binstead are 

 chiefly those of univalve gasteropoda, and be- 

 long to genera common in our rivers and 

 lakes. The Planorbis, or discoidal river-snail, 

 I 'I. I. ligs. 1, 2,) may be distinguished by the 

 .shell being involuted or coiled up in a nearly ver- 

 tical plane; five or >i\ specie's have been found. 



