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exploration of that complicated succession of freshwater and fluviomarine 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 limestone 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 Paleotheria and other extinct quadrupeds, which Cuvier had long before described. It followed from the correction here alluded to, that the mammiferous fauna of Binstead held a much higher place in the Eocene series than the Headon beds, and, consequently, than the contemporaneous Hordwell strata of Hampshire, in which other quadrupeds than those of Binstead, including amongst them the Paloplotherium of Owen, had been detected. Between these two divisions, 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 species of mollusca.
In addition to all these results, Prof. Forbes brought to light an entirely new member of the British tertiary series, hitherto overlooked. 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 recognized. These would be classed by many geologists of the continent 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 arbitrary line of demarcation, to denominate the Bembridge beds Eocene, according to received usage, and to distinguish the Hempstead strata as Miocene.
Always an active and influential member of the Geological Society, Prof. Forbes became its President in 1853. His anniversary address
