296 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1926 
been shown that not only do the deposits span a longer interval of 
time than is here suggested but there were gaps and periods of sharply 
contrasted climatic changes included within its limits. There is 
often little to be gained by trying to restrict the use of a scientific 
term that has been accepted popularly in a wider sense. On the 
other hand, loess and its origin is of general interest and yet has 
aroused much discussion that would have been seen to be beside the 
point had the theorists realized they were talking of a thing that 
was not one, but many! Moreover, in this case even the broad range 
of variation covered by the word as used in Europe and America is 
exceeded if we use it to include deposits definitely distinct from true 
loess in composition, texture, habit, age, origin, and fossil content. 
By recognizing these perfectly observable differences there is reason 
to hope that we may in the near future solve the remainder of the 
puzzles presented by the loess in China. 
BIBLIOGRAPHY 
Nore.—This list is in no sense exhaustive, Since descriptive passages are to 
be found in almost every book of travel. The references noted below make 
either original scientific contributions or Summarize conveniently the results of 
the research of others. 
1. Andersson, J. G., Essays on the Cenozoic of China, G. 8S. C. Mem. A. 38, 
Peking, 1923. 
2. Clark and Sowerby, Through Shen-kan, Fisher Unwin, London, 1912. 
3. Fuller, M. L., Some unusual erosion features in the loess of China, Geo- 
graphical Review, XII, +, October 4, 1922, New York, p. 570 ff. 
4. Grabau, A. W., Principles of stratigraphy, Seiler & Co., New York, 19138. 
. Licent, E., Comptes-rendus de dix années (1914-1923), Pub. Musee Hoang 
Ho Pei Ho, Tientsin, No. 2, 1924. 
6. Lyon and Buckman, Nature of properties of soils, Macmillan, New York, 
1 | 
1922. 
7. Merrill, G. P., Rocks, rock weathering, and soils, Macmillan, New York, 
1921. 
8. Pumpelly, R., Relations of Secular Rock Disintegration to Loess, Glacial 
Drift, and Rock Basins, Am. Jour. Sc. and Arts, xvii, February, 1879. 
9. Pumpelly, R., Geological researches in China, Mongolia, and Japan, Smith- 
sonian Contributions to Knowledge, Vol. XV. Washington. 
10. v. Richthofen, F. F., China, Berlin, 1882, Vol. II, ete. 
11. Walther, J., Das Gesetz der Wustenbildung, 2nd Ed. Leipsig, 1924. 
12. Willis and Blackwelder, Research in China, Carnegie Inst. of Washington, 
Vol. I,, Part I, 1907. 
13. Wright, W. F., Origin and distribution of loess in Northern China and Cen- 
tral Asia. Bull. G. S. A., vol. 18, p. 127, Rochester, 1902. 
14. Yih, L. F., Geology of the western hills of Peking, G. 8S. C. Mem. A. 1, 
Peking, 1920. 
