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exploration of that complicated succession of freshwater and fluvio- 

 marine beds ; and when we reflect how many able geologists had 

 gone before him in this field, we may well marvel at the richness of 

 the harvest which he reaped. Among other novel conclusions, he 

 showed that certain strata called the Headon beds in Alum Bay had 

 hitherto been incorrectly identified in age with the Bembridge lime- 

 stone of Whitecliff Bay at the opposite or eastern end of the island. 

 These Bembridge beds, which belong to the same division as the 

 well-known calcareous building-stone of Binstead, were recognized 

 as the true equivalents in age of the celebrated gypseous series of 

 Montmartre near Paris, containing similar remains of Puleotheria and 

 other extinct quadrupeds, which Cuvier had long before described. 

 It followed from the correction here alluded to, that the mam- 

 miferous fauna of Binstead held a much higher place in the Eocene 

 series than the Headon beds, and, consequently, than the con- 

 temporaneous Hordwell strata of Hampshire, in which other qua- 

 drupeds than those of Binstead, including amongst them the Palo- 

 plotherium of Owen, had been detected. Between these two divi- 

 sions, called by Forbes the Bembridge and the Headon, he found 

 another, which he called the Osborne or St. Helen's series, also of 

 fresh and brackish-water origin, and distinguished by peculiar spe- 

 cies of mollusca. 



In addition to all these results, Prof. Forbes brought to light an 

 entirely new member of the British tertiary series, hitherto over- 

 looked. Near Yarmouth, in the Isle of Wight, the most elevated 

 ground formed by tertiary deposits is called Hempstead Hill, in 

 which strata corresponding in their fossils with the Limburg beds of 

 Belgium or the Gres de Fontainebleau in France, were recog- 

 nized. These would be classed by many geologists of the conti- 

 nent as Lower Miocene ; but Prof. Forbes inferred, from the gradual 

 passage which he traced between them and the subjacent Bembridge 

 series, that the whole should rather be regarded as Upper Eocene. 

 In a word, he declared it to be impossible, without drawing an arbi- 

 trary line of demarcation, to denominate the Bembridge beds 

 Eocene, according to received usage, and to distinguish the Hemp- 

 stead strata as Miocene. 



Always an active and influential member of the Geological Society, 

 Prof. Forbes became its President in 1853. His anniversary address 



