《丁文江海外書信集初編》：

　　Please don't misunderstand me.The Geological Survey of China claims no monopoly of anykind.Nothing is more welcome， to me than that the scientific abroad begin to be more alive to theimmense possibilities of scientific discovery in China， and it has been the settle policy of the Surveyto do all that is in its power to help foreigners coming over here to work.Many Americans includingMr.Andrews himself will be able to substantiate this statement.We realize most clearly that China ispractically an unknown continent and the more people work at it the better known it will become.Butapart from the fact that Dr.Andersson and the Geological Survey have been working at the very sameproblems for the last two years， and that therefore in justice and fairness to them， their priority shouldbe taken into consideration， it is certainly in the interest of everybody as well as that of science toarrange cooperation and division of labor instead of undesirable competition.I may suggest a concreteexample to show what I mean.It is known that in northern China the Hipparion fauna dominates toa large extent but the country on the southern side of the Yangtze river， especially the southwesternprovinces， Yuanan and Szechuan， seems to have a different history.

　　……