of 



of 



By E. R. BANKES, Esq., assisted by the Rev. 

 0. R. DIGBY. 



PLATE XI. ' 



WING to its natural characteristics the Isle of 

 Purbeck affords, as might be expected, a most 

 interesting field for the Entomologist. Forming 

 as it does the central portion of the coastline 

 between two such noted localities as the Isle of 

 Portland and the Isle of Wight, and embracing 

 on its landward side a portion of the extensive heath district in 

 which a great part of the New Forest itself may not improperly 

 be included, it can hardly fail to be rich in variety of insect 

 life. In spite of the small extant of its area, its greatest dimen- 

 sions being only 12 miles in length by 10 miles in breadth, it 

 presents geologically a series of strata seldom met with in such a 

 limited space ; the Kimmeridge Clay and the Oolite are followed 

 by the Purbecks, the Hastings Sands, the Gault, the Green 

 Sand, the Chalk, and the Tertiaries in quick succession, and as 

 a natural consequence the Flora bears a very varifd character, 

 for it will be found, though many plants are common to all, that 

 every series of strata has its own peculiar botany.* 



The island is divided naturally into two parts by the long 

 range of chalk hills which stretches from the Old Harry Eock to 

 the coast at Worbarrow. To the south of this range the country 



* See Furbeck Society Papers, 1855. 



