A photo taken in 1901 by Dr Edward Smyth Crispin, showing the earthen mound associated with the Nuer Prophet Ngundeng. Seligman describes it in his list as a grave pyramid, possibly since he was informed that Ngundeng was buried within his hut at the base of the mound.
From the appearance of the earth on the pyramid, it resembles the state in which it appears in other 1901 photographs by Crispin published as Plates XXI Fig.1 & 2 (facing page 232) of C.G. & B. Seligman’s Pagan Tribes of the Nilotic Sudan (London, Routledge 1932), as well as Plates XXVa & b of Evans-Pritchard’s The Nuer (OUP 1940), where the photograph is credited to Crispin.
The probability is therefore that this is another of Crispin’s photographs of the mound from 1901, from a different aspect. Further research will hopefully shed more light on this.