Mervyn Herbert Nevil Story Maskelyne (3 September 1823 – 20 May 1911) was an English geologist and politician.

Maskelyne was also a pioneer of photography and an associate of Fox Talbot.

Mervyn married Thereza Mary Dillwyn-Llewelyn (1834 – 21 February 1926) - Welsh astronomer and pioneer in scientific photography - on 29 June 1858.

Their daughter Mary married writer and politician Hugh Oakeley Arnold-Forster on 29 July 1885, and Hugh and Mary's granddaughter Vanda Morton published Nevil's biography in 1987 (see references).

Their daughter Thereza was an advocate for domestic science who married physicist Arthur William Rucker in 1892.