I'm not sure there are any descendants left in the male line - I've been looking for any for years.
I think only two of the Rev Naunton Thomas Orgill Leman's sons married - Robert (1799-1869) & The Rev Thomas (1804-1873). Thomas died without issue, but Robert married twice and had children by both wives.
By Isabella Twysden he had a son, Naunton (1825-1904), who married Rosa E Ross. They in turn also had a single son, Robert Naunton Leman (1870-1927), who in 1913 married Gertrude Bloomfield. They had just one child, Beryl Twysden Leman, born in 1914: she died without issue in 1999.
By his second wife, Ellen Maria Ross, Robert (d 1869) had four more children, one born posthumously, the other three when he was in his 60s! There was a son, Anderson Thomas John Leman (b 1862) and three daughters. I lost track of Anderson for a long time, but I now believe he moved to Australia in 1885, and died in Queensland in 1935: I've so far been unable to find out if he had a family.
Of the daughters, Maud (1866-1878) & Ethel (1869-1941) died without issue, while Beatrice (c1864-1945) married Frederick Wm South in 1902 - another daughter, "Fanny", is mentioned in her uncle Rev Thos's will, but I suspect this must have been a family nickname for one of the others. Beatrice & Fredk had one son, Frederick Ross Naunton South (1903-1987), an electrician in Yeovil (how are the mighty fallen!); this Frederick seems (from his mother's will) to have had at least one child, a daughter, Lois, living in 1939 - but I've so far failed to find any sign of his marriage or children's birth. I'll go and look for his will when I get a moment.
There are certainly descendants of the Rev Naunton Thomas Orgill Leman's daughter, Frances, who married Commander Molyneux Shuldham, RN, in 1820 (and died in 1866) - there may perhaps be others of the Barlee & Gee families, too, I've not looked into them yet.
I own a pair of 1834 portraits of the Rev Naunton T O Leman & his wife Henrietta, and the reason for my interest. I'll take some photos and post them here another day.
Ossie Bullock