The Zia Sand Formation, new early to medial Miocene beds in New Mexico

first time, crops out at several localities in the Jemez Creek Valley and in a few of the canyadas along the northern part of the Ceja del Rio Puerco in Sandoval County, New Mexico. These are the first early Miocene deposits reported from New Mexico for which conclusive fossil evidence for time-unit correlations (Wood et al., 1941) is available. Field work by Frick Laboratory parties, under my direction during 12 seasons since 1946, has resulted in the discovery of fossils at many localities and at many horizons in the Jemez Creek area, the Ceja del Rio Puerco area, and the Gabaldon badlands. The work was a part of the exhaustive investigations of the paleontology, geology, and stratigraphy of the Santa Fe Formation started in 1924 by Dr. Childs Frick and continued until his death in 1965. An extensive report, "The Stratigraphy of the Santa Fe Group," by the author and John C. Blick is now in preparation, and this will deal in great detail with the broader aspects of the geology and stratigraphy of the areas that are described briefly in this preliminary report. Both of these reports are directly the result of Dr. Frick's long-continued interest in the fauna of the Santa Fe beds. It is a pleasure to acknowledge his constant and kindly support. I am indebted to the members ofthe Frick Laboratory for aid and advice in the preparation of the manu-script and especially to Mr. Raymond Gooris for help with illustrations