vi FLORA OF JERSEY. 



From a physical point of view, Jersey is a part of France. Liie 



the other Channel Islands, it is merely an excrescence tipoii a 



submerged platform of rocks which extends mider water from 



the French coast. An elevation of land to the extent of about 



30 fathoms would fill up most of the Bay of St. 



and Latham, Malo, and the surrounding sea is so full of rocks and 



■ ^' ^' reefs (some of them, Les lies Chausey, Les Min- 



quiers and the Ecrehos Eocks, of considerable extent) as to render 



the navigation difficult and dangerous in hazy weather. At 



present the sea appears to be gaining very slowly upon the 



laud. Without accepting the venerable fable that the Bishop 



„ ,,„ of Coutances was once able to cross the silver 



Nauru, V- W8. 



streak that then divided Jersey from France on a 



plank, it may safely be assumed that the Island was once much 



larger than it is now. The fall of the tide, which is sometimes 



over 40 feet, lays bare enormous stretches of wild, desolate rocks 



which were once land ; and at various points of the coast detached 



rocks may be seen which are covered with the same superficial 



deposits as the nearest shore, and are obviously nothing but 



broken fragments of the laud, and not rocks which have emerged 



from the sea. Again, there are traces of a " sub- 

 "'"'^4™' merged forest " in St. Ouen's Bay, near L'Etac, and 



the character of the peat deposits on the low-lying 



land seems to suggest a derivation from a larger land area than the 



present. On the other hand, the presence of raised beaches at 



various levels seems to prove that in still earlier times the island 



was buried more deeply than it is now in the sea.='= 



The rocks of Jersey consist almost entirely of granite (or 



syenite), metamorphic schists and porphyries, with an ancient 



conglomerate in the north-east. It is doubtful 

 Nourij, p. 103. ° 



whether there is any unaltered sedimentary rock 



in the Island. Chalk and limestone are entirely absent. In- 

 equalities in the original surface are largely filled up with super- 

 ficial quaternary deposits of brick clay or brick earth, generally 

 unstratified. In some of the low-lying districts (e.g., under St. 

 Helier's) there are deposits of peat, gravel, and stiff blue clay. 



* The best account of the geology is contained in " Ge'ologie de Jersey," 

 by Father C. Noury, S.J. Cf. also Dr. A. Dunlop's paper "On the Super- 

 ficial Deposits of Jersey and Guernsey," in the Transactions of the 

 Guernsey Society of Natural Science for 1897. 



