Ammianus Marcellinus was a historian who wrote a catalogue on the fauna of Egypt in the 4th century A.D., in which he included a sad note about the southward retreat of the hippopotami, once plentiful in the delta. He took particular interest in crocodiles and gives a fanciful version of the relationship between the crocodile and the ichneumon which preyed on the eggs of the female. He wrote that the Egyptian people were, as a rule, somewhat swarthy and dark of complexion, rather gloomy looking, slender and wiry, excitable in all their movements, quarrelsome and most persistent in getting their way.' He also claimed that the very best land, under an ideal inundation, would return a seventy-fold yield.