The region in which the expedition worked had previously been visited by several naturalists. The foremost collections are those made in the early seventies of the last century by the two Yarkand Missions under T. D. Forsyth, whose ornithological results were reported upon by Henderson and Hume, Scully, and Sharpe. Other contributions to the ornithology of the Tarim basin are due to Menzbier, Przewalski, and Schalow, while Dr. W. L. Abbott's travels added considerably to our knowledge of the bird-life of the western Himalayas and Eastern Turkestan. In the Tian Shan Mountains, Severtzow, Almásy, and secured extensive collections. Kashmir and Ladak have lately attracted the attention of various ornithologists, among whom Meinertzhagen, Osmaston, and Whistler may particularly be mentioned.