High-precision 40Ar/39Ar geochronology and the advent of North America’s Late Cretaceous terrestrial fauna

A densely sampled, diverse new fauna from the uppermost Cedar Mountain Formation, Utah, indicates that the basic pattern of faunal composition for the Late Cretaceous of North America was already established by the Albian-Cenomanian boundary. Multiple, concordant 40Ar/39Ar determinations from a volcanic ash associated with the fauna have an average age of 98.39 ± 0.07 million years. The fauna of the Cedar Mountain Formation records the first global appearance of hadrosaurid dinosaurs, advanced lizard (e.g., Helodermatidae), and mammal (e.g., Marsupialia) groups, and the first North American appearance of other taxa such as tyrannosaurids, pachycephalosaurs, and snakes. Although the origin of many groups is unclear, combined biostratigraphic and phylogenetic evidence suggests an Old World, specifically Asian, origin for some of the taxa, an hypothesis that is consistent with existing evidence from tectonics and marine invertebrates. Large-bodied herbivores are mainly represented by low-level browsers, ornithopod dinosaurs, whose radiations have been hypothesized to be related to the initial diversification of angiosperm plants. Diversity at the largest body sizes (>106 g) is low, in contrast to both preceding and succeeding faunas; sauropods, which underwent demise in the Northern hemisphere coincident with the radiation of angiosperms, apparently went temporarily unreplaced by other megaherbivores. Morphologic and taxonomic diversity among small, omnivorous mammals, multituberculates, is also low. A later apparent increase in diversity occurred during the Campanian, coincident with the appearance of major fruit types among angiosperms, suggesting the possibility of adaptive response to new resources.

I. Sermons, 1709-1724

This series contains seventeen handwritten sermons composed by Nicholas Sever and delivered in the Boston area between 1709 and 1722. Following the completion of his Master's degree at Harvard in 1704, Sever preached in towns around New England including Haverhill in 1709, Dover, New Hampshire (where he was ordained in 1711 and remained until 1715), and in Cambridge as part of his duties as a Harvard Tutor between 1716 and 1728. During these years, Sever also filled in for ministers in nearby parishes. Sever's sermons reflect these engagements, and he occasionally noted the dates and locations where the sermons were delivered in the margin of the first page of the sermon.

Abstracts of sermons preached at Harvard College, 1728-1729

Small notebook containing notes kept by John Winthrop on sermons he attended between September 1, 1728 and October 19, 1729, while he was an undergraduate at Harvard College. The volume contains one-to-two page entries on specific sermons and provides the biblical text and related doctrines, questions, and conclusions. The inside back cover contains a handwritten index of the minister who gave the sermon, most often Nathaniel Appleton.

Sermons : manuscript, 1694-1695

Autograph manuscript, signed, probably written in Boston.