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Antennaria rosea (Asteraceae: Inuleae) is a herbaceous perennial that reproduces by gametophytic apomixis and is widespread in the cordillera of western North America, ranging from New Mexico to Alaska. In the overall pattern of population structure in A. rosea, the majority of the population are polyclonal, although the average number of clones per population is relatively small (X = 3.1). In general clones are restricted to one or two populations (X = 1.1) and, therefore, very few widespread clones exist. The subarctic populations are characterized by relatively low amounts of clonal diversity when compared with those from southern latitudes (X = 2.0/population). Clonal diversity is negatively correlated with latitude, longitude, and elevation of the sites. It seems unlikely that A. rosea survived the last glacial episode in the northern glacial refugium. Beringia, and a more likely scenario for the phytogeographic pattern of clonal diversity is one that envisions A. rosea surviving the Wisconsinan south of the glacial margin or perhaps arising in the same region at the end of the Wisconsinan. New clones probably arise via crossing of facultatively apomictic clones of A. rosea to their sexual progenitors. As most of the eight sexual progenitor taxa are absent from the north, new clones cannot easily arise there. The lack of clonal diversity in the subarctic and arctic could be the result of a combination of recent migration and lack of sexual progenitors in the region.

Species of Cheilymenia, Coprobia, and Scutellinia of the Ciliarieae (Humariaceae) are studied by electron microscopy. They share the same type of ascosporogenesis, although only Cheilymenia and Corpobia form spore sheaths on their ascospores, and epispore layers are formed the primary wall is deposited between spore-delimiting membranes. The manner of formation of epispore layers is very similar to that in the genus Aleuria. Gradual condensation of the secondary wall material in the perisporic sac is consistently found. Globular bodies with rodlet contents are found in the perisporic sac of Cheilymenia and are different from those found in Aleuria. Vacuolation occurs in the perisporic sac, within which ornaments are almost completely formed. During the condensation of secondary wall material, a translucent zone similar to that commonly found in Ascobolus and other coprophilous fungi is formed between the epispore layer and the ornaments.

Hydnobolites cerebriformis is a widespread species of hypogeous ascomycetes found in both the United States and Europe. The ascomata are from 0.5 to 3.0 cm in diameter, with a thin cortical region surrounding clusters of globose to saccate asci arranged near veins within the medullary region. Because hymenial chambers were believed to lead to the surface of the ascomata, the genus was until recent years placed among Tuberaceae. The size, shape, and arrangements of asci and the pigmentation of ascospores, however, have led recent workers to place Hydnobolites in the Terfeziaceae. Cytological and ultrastructural features of asci, septa, and spore wall ontogeny in H. cerebriformis reveal a number of characters that link Hydnobolites to the traditional epigeous Pezizaceae. These include the presence of electron-dense, biconvex bands in septal pores of asci, dextrinoid and weak bluing reaction of asci in iodine, and a type of spore wall deposition similar to members of Pezizaceae.

Tertiary fruit remains of Pteleaecarpum, which we recently interpreted as valves of winged capsules of an extinct sapindaceous genus, are now recognized as belonging to a living genus of Tiliaceae. The fossil fruits, which are common in the Tertiary of western North America, Europe, and Asia, are virtually identical in morphology and anatomy to fruits of Craigia W. W. Smith and Evans, an extant tiliaceous genus of southern China. Accordingly, we now present the following new combinations for fossil taxa: Craigia bronnii (Unger) and Craigia oregonensis (Arnold).