In the Dr. Jacobus survey definite penis size differences on a basis of race were detected. The largest Arab penises were found to be between eight and ten inches; but it was among the Muslim Sudanese that Jacobus found “the most developed phallus” – notably “one of the maximum dimensions, being nearly 12 in. in length, by a diameter of 2- in.” The hardy researcher remarked that this was “a terrific machine” – “more likely the penis of a donkey than of a man.” He concluded that the “Sudanese Negro possesses the largest genital organ of all the races of mankind”. In a less extensive survey, but equally interesting, Dr. Robert Chartham measured erect penises for groups of men of various nationalities. The largest organs for each nationality were as follows: English – 10½ in.; West German – 8½ in.; Negro – 7½ in.; French – 7¾ in.; Danish 8 in.; American – 7¾ in.; and Swedish 7¾ in. The groups were small, ranging from only 9 to 121 individuals; nevertheless the data acquired are not without significance.