ABSTRACT In 1921, exploration for oil and gas was substantially assisted by the discovery that foraminifera could be used to more accurately correlate subsurface strata. This changed everything. It was at a time when the petroleum industry did not have the benefit of geophysical logging tools or seismic mapping capabilities. Micropaleontology was quickly embraced by industry and almost instantly expanded to global use. Three young women were responsible for this technological breakthrough—Alva Ellisor, Esther Applin née Richards, and Hedwig Kniker. They were hired by Texas oil companies in 1920–1921 for the express purpose of using paleontology, specifically macropaleontology, to try to solve the Gulf Coast stratigraphic problems. They were encouraged to collaborate—in itself an unusual phenomenon in the highly competitive oil and gas business—which they did with grace and skill and which led to their discovery of foraminifera as a major biostratigraphic tool. However, their role was downplayed over time, and by 1975 credit for this important technology was shifted to four men—men who had themselves failed to recognize the application, in fact one had ridiculed the idea, but who quickly embraced it when the women presented their evidence. It is time to recognize their revolutionary contribution to the improved economics of oil-finding as well as to the sciences of biostratigraphy and paleontology.

Abstract: The Permian Period is one of the most varied times, not only in oceanic environments, but also for the evolution of the radiolarian assemblages. Permian radiolarians have been extensively studied, and great progress has been achieved recently in their biostratigraphy. Seventeen Permian radiolarian zones are summarized here. Among these, seven zones are assigned to the latest Carboniferous–early Permian, namely (in ascending order): the Pseudoalbaillella bulbosa Assemblage Zone, the Pseudoalbaillella u-forma – Pseudoalbaillella elegans Assemblage Zone, the Pseudoalbaillella lomentaria – Pseudoalbaillella sakmarensis Assemblage Zone, the Pseudoalbaillella rhombothoracata Interval Zone, the Albaillella xiaodongensis Assemblage Zone, the Albaillella sinuata Abundance Zone and the Pseudoalbaillella ishigai Abundance Zone. Five zones are attributed to the middle Permian, including the Pseudoalbaillella globosa Interval Zone, the Follicucullus monacanthus Interval Zone, the Follicucullus porrectus Interval Zone, the Follicucullus scholasticus Interval Zone and the Follicucullus charveti Interval Zone. Five zones belong to the middle Permian–late Permian, including the Albaillella cavitata Interval Zone, the Albaillella levis Interval Zone, the Albaillella excelsa Interval Zone, the Albaillella triangularis Interval Zone and the Albaillella yaoi Abundance Zone. These Permian radiolarian biozones and their correlations with conondont zones or other chronostratigraphic schemes are discussed. The phylogenetic model of radiolarians through the Permian Period is also revised.