Cairo, met Stromer during the winter of 1901–1902, and got along very well. Markgraf was Stromer's Sammler, or fossil collector, for 10½ years, and became Stromer's friend. Markgraf, however, was often ill. It is unclear whether the cause was malaria, intestinal bleeding from typhoid, or chronic amebic dysentery. The plan for the expedition contained three parts; first, Stromer and Markgraf would travel northwest from Cairo to Wadi el Natrun. After exploring the area for a few weeks, they would return to Cairo, replenish their supplies, and afterwards head south to Luxor to explore the eastern slopes of the Nile Valley. The last part of the expedition would be spent exploring the Bahariya Oasis. Beginning of the expedition Stromer and Markgraf began the expedition with the goal of discovering fossil mammals to support Stromer’s theory of an African origin of humanity. Stromer's 1910 journals from Wadi el Natrun reveal that he worked all through the day, hiking for miles, climbing hills, and hammering pieces of rock from outcroppings throughout the valley. He discovered sharks' teeth, broken shells of ancient turtles, and the occasional jaw of a prehistoric crocodile. Despite these discoveries his failure to uncover ancient mammals left him disappointed and he returned to Cairo. Markgraf, who stayed in Wadi el Natron after Stromer’s return to Cairo, discovered the skull of Libypithecus markgrafi. The second stage of the expedition took them to a location far up the Nile in December. This location yielded little success. The third stage of the expedition was delayed due to Markgraf becoming ill and being unable to proceed to the Bahariya Oasis. Stromer found a dragoman who could function as a guide and translator. On 3 January 1911, the expedition left for the Western Desert. The caravan was significantly slowed as they had to find grazing areas for the camels because one of the team members hadn’t bought fodder for the animals. After more than a week of walking, they arrived in the Bahariya Oasis on January 11, 1911. Due to the inaccuracy of the understanding of the geologic history of the Bahariya Oasis in 1911, Stromer erroneously believed the oasis to date to the Eocene rather than Cretaceous. Discoveries On 14 January, the weather eased and the expedition was able to begin. That first day, Stromer was able to find a fossilized shark vertebrae, fish teeth, and some petrified wood. On January 18, he found