Thirty-five species of planktonic Foraminifera belonging to eight genera are discussed and referred to previously recorded and illustrated forms. These speciés comprise a small part of several foraminiferal assemblages taken from samples collected from the Miocene Lubuagan, Callao, and Cabagan formations exposed along the Cabagan River in Eastern lsabela. Brief discussions on the ages and planktonic composition of the different faunas from the three geologic formations are given in addition to lithologic descriptions. Ecologic conditions during their respective time of depositions are likewise included. The distribution of the planktonic species in each sample is shown in 3 tables.

The thirty-five species are systematically treated in accordance with Bolli, Loeblich, and Tappan’s (1957) modified classification of the planktonic forarniniferal families: Hantkeninidae, Orbulinidae, and Globorotalidae.