Franklin named these two forms "B" and "A" respectively. (The biological functions of A-DNA were discovered only 60 years later.) Because of the intense personality conflict developing between Franklin and Wilkins, Randall divided the work on DNA. Franklin chose the data rich "A" form while Wilkins selected the "B" form because, according to his autobiography, Wilkins' preliminary pictures had hinted it might be helical. The X-ray diffraction pictures, including the landmark "Photo 51" taken by Franklin's student Gosling at this time, have been called by John Desmond Bernal as "amongst the most beautiful X-ray photographs of any substance ever taken".