River Mole in 1613. In John Speed's 1611 map of Surrey this stretch of the river is denoted by a series of hills accompanied by the legend "The river runneth under". However the river's name is unlikely to have derived from this behaviour: The "Oxford Dictionary of English Place Names" suggests that "Mole" either comes from the Latin "mola" (a mill) or is a back-formation from "Molesey" (Mul's island). In John Rocque's 1768 map of Surrey, the name "Moulsey River" is used. In common with much of the rest of the Weald, the earliest evidence of human settlement along the Upper Mole
River Mole fast swimming mayflies and riffle beetles. The beautiful demoiselle ("Calopteryx virgo") disappeared from the River Mole during the 1960s owing to deteriorating water quality, but has since recolonised. The white-legged damselfly ("Platycnemis pennipes") is also found along the river and the downy emerald ("Cordulia aenea") is found between Box Hill and Leatherhead. The Mole is one of only three locations in England where the river shingle beetle ("Meotica anglica") is found. A nationally scarce species which is locally common on the River Mole is the greater dodder ("Cuscuta europaea"). The Mole catchment area includes twelve Sites of Special Scientific Interest