Some of the material is in notebook binders. One notebook relates to the National Geographic Society and Yale Peruvian Expedition of 1914-1915 and includes general orders of the expedition. Another notebook has to do with economic plants, and the others relate to cultivated plants. A group of notes have to do with comparisons of Quichua and Polynesian plant names. The rest of the material are note slips. Much of the data appears to come from published sources.