Abstract. The Last Interglacial deposits formerly exposed along Histon Road, Cambridge, have been cored and an attempt made to integrate the analyses of plants and mollusca. The beds cored are referred to zone g of the Last Interglacial and to zone h-i, a symbol used to indicate that, although there appears to be no unconformity, the Picea zone h is absent in this, the only known British section of this part of the Last Interglacial. No trace of zone f was found. In order to analyse the palaeoecology, the macroscopic plant remains and mollusca were recorded from 41 subdivisions, each representing on an average 15 cm of core. Some 3000 fruits and seeds and 16000 mollusca were recovered. These have been divided into environmental and climatic or distribution groups and the significance of variations of these groups discussed. The plant remains and the mollusca seem to present a consistent picture of conditions varying from riverside marsh to full stream conditions, such as might be expected from a shifting, aggrading river.