An Eocene (45 Ma) flora from Thunder Mountain caldera shows that montane conifer forest species from upper slopes descended to interfinger with mixed conifer-deciduous hardwood forest on the caldera floor then near 1700 m. Most species are allied to those in the western United States, but a few genera are in China. Precipitation was near 100 cm yearly, with most in summer.

This flora of 70 species is dominated by deciduous trees, many with descendants in China. Precipitation was 890 mm, mean annual temperature 12.5 C, the annual range 10 C, and freezing rare. Elevation was about 1000 meters. Comparison with the Horse Prairie flora, 30 miles east and across the present continental divide, indicates that the divide was then low and discontinuous, with warmer climate to the east."

The author describes forty-two fossil taxa recovered during a study of the San Timoteo Badlands that used magnetobiostratigraphy to develop a temporal framework for addressing the tectonic evolution of southern California over the last 6 million years. For the Pliocene, small mammals are an effective means of correlating a magnetostratigraphy to the Geomagnetic Polarity Time Scale when radioisotopic dates are unobtainable.

This is a study of the Miocene Carmel flora of California, an evergreen laurel-oak forest that grew in a mild temperate (mean annual temperature of 15 degrees C), frost-free climate, with annual precipitation of about 760 mm (30 in.). Collectively, the Carmel and other Miocene floras like the San Pablo and Temblor (broad-leafed deciduous trees, with few evergreen species), the Puente (evergreen oak forest with chaparral species), the Mint Canyon, Ricardo, and Tehachapi (numerous arid subtropical scrub associated with oak woodland and chaparral species) suggest they foreshadowed a similar...

The highly variable North American red crossbill complex has presented one of the most controversial problems in avian systematics. Although crossbills wander nomadically and breed all year, they have not become homogenized in bill and body size. This study suggests that this crossbill complex contains several distinctive sibling species that breed sympatrically and show ecological differences.

Approximately 12 million years before the extinction of the dinosaurs, a diverse terrestrial fauna inhabited what is now northcentral Montana. The author describes and evaluates the systematic relationships of the large mammalian fauna of this area, which included rodent-like multituberculates, primitive therians, marsupials, and early eutherian mammals, and also analyzes the biogeography of mammalian faunas of the Judithian age.

Royal treasury records of annual auctions of Indian tributes are the source of price history for sixteenth-century Nueva Galicia. Using this data, this book determines that from 1557 to 1598 the prices of some commodities such as maize rose more than in the neighboring Audiencia of Mexico, whereas other prices, such as those for wheat, fell.