Puerto del Triunfo, Dept., Usulutan Dec, 28, 1926 - Jan, 15, 1926 Oryzomys Ochraceous-rumped mouse- Only four specimens of this species was taken by me a Puerto del Triunfo. Nos. 10938 and 10951 were taken in the same trap which was set on a dead leaf and vine covered log near a carreta trail through dense and tangled second growth. There were many traps set in similar places in this immediate vicinity. The specimens were taken at least one- half of a mile from one of the little forest or jungle streams. Nos. 10992 and 11013 were taken at the base of tall heavy grass in a brushy banana grove. (see Oryzomys notes) Here I found this mouse in association with other Oryzomys, Sigmodon and spiny-pocket mice, while in the second growth I found only Oryzomys and [illegible] spiny-pocket mice with them. Stomach contents showed white starchy pulp. At its advanced stage of digestion I was unable to tell whether it was seed or plant pulp.