For several reasons the present seems to be a favorable time to make a brief survey of the literature of climatology, and also to indicate the gaps which are as yet unfilled. This matter concerns chiefly those whose sole or at least main field is research or instruction in climatology. But there are; few branches of science the workers in which do not, at some time or other, need information on the world's climates. Geographers in particular, but also geologists, botanists, zoologists, medical men, and many others, often reach a stage in their investigations which leads into a blank wall unless the climatic factor is taken into consideration. Into the writer's office there come year after year at frequent intervals graduate students of botany, of zoology, of geology, of anthropology and ethnology, of engineering, all seeking information about the climate of some area with which they are concerned, and a knowledge of which is essential in the prosecution of their studies. These students have suddenly realized that they need to know something about climate, and they are almost wholly ignorant as to how and where to seek the desired information. Almost as much help has, in the long run of the years, been given by the writer to such men, concentrating in other fields, as to those who were devoting themselves primarily to meteorology and climatology.