Excursion to Herm. 



129 



but the small one, Belvoir Bay, has the reputation of furnish- 

 ing more perfect shells. The beaches are composed to a 

 considerable depth of broken shells, but specimens in good 

 condition are tolerably numerous. The shells are mostly those 

 of creatures inhabiting the adjacent seas, living specimens of 

 which can be found on the surrounding rocks and weed or 

 dredged from deep water. Sometimes, however, collectors have 

 found among the debris, shells from distant parts and occasion- 

 ally rare ones. 



It is not easy to see why such a deposit should be confined 

 to this special locality ; why for instance a similar accumulation 

 should not be formed on the east of Guernsey, a little study of 

 the conformation of the district and of the set of the tides will 

 give some reasons for its occurrence here. 



The strong tide which rushes like a powerful river between 

 the main island and the Godinent and other rocks on the North, 

 and the corresponding current through the Percee* on the S. 

 on entering the Great Eussel are checked and lost in the main 

 cross current and spread out with greatly diminished force to 

 cover the intermediate area, east of Herm. The stilled waters 

 drop the sand they held suspended in them, while the lighter 

 material, the shells, are carried further and disposited in the 

 quiet reaches along the east coast. Storms and the action of 

 the tide then throw them up on the beach. 



While the ladies were thus pleasantly employed collecting 

 the prettiest and most beautiful shells, several of the gentlemen 

 started across the sands spreading so extensively eastward 

 from the pier. Here they found abundance of life interesting 

 even to those who had not specially studied marine zoology ; 

 quantities of small crustaceans, sea hares (Aplysia), specimens 

 of EoiiSy Chitons, Botryllus, and various sand stars (Ophiocoma) 

 and others. 



*The tide through the Percee runs for nine hours to the South into 

 the Great Russel with great strength, but only for three hours to the 

 North and that only faintly.— (Ch. Is. Pilot 1870.) 



