Abstract During the nineteenth century Europe and then America were the focal points for major advances in the study of palaeontology and the great, often acrimonious, debate on evolutionary theory. Natural history was one of the great educational disciplines of the day and those involved were part of an educated elite who practised as medics, clergymen, chemists and anatomists. Some were shy and retiring, others forceful even bombastic, sometimes evil by intent. Many were driven by fame and it was their wish to discover the best, the biggest and the most important specimens they could get their hands on. Others were great orators who could defend a cause; some were the first of many who became diligent and careful in the collection and storage of material or brilliant field scientists who taught us the importance of observation, data gathering and interpretation of sedimentary successions worldwide. Being considered worthy of joining such an elite social, scientific circle was an immense tribute to their contribution to the natural sciences. It was an honour denied William Smith who lacked the educational background of the middle classes of the time, but given in abundance to the Italian scientist Giovanni Capellini who was born into an upper middle-class Italian family and who received a classic ecclesiastical training before venturing into the natural sciences. Supplementary material: A list of selected publications by Giovanni Capellini (1858–1907) is available at http://www.geolsoc.org.uk/SUP18417 .

Abstract Baron Achille de Zigno (1813–1892) of Padua published dozens of articles on the early Mesozoic floras from the Venetia region of Italy. His magna opera , however, were the two volumes of the Flora fossilis formationis oolithicae (Volume 1 (1856–1867) and Volume 2 (1873–1885), Padua University Press, Padua). In these he aimed to put the Venetian Jurassic plants in context with what were then considered oolitic floras from around the world. Like many of his contemporaries, his research has been revised both taxonomically and stratigraphically, so that the fossil plants he described from the calcari grigi are now regarded as older than Middle Jurassic. His collection of over 3000 specimens of Italian fossil plants, now kept in the University of Padua, continued to attract researchers during the 20th century from across Europe who used light microscopy to investigate them. Today electron microscopy is being applied to Baron Zigno’s specimens that are of importance not only as representatives of a rare Middle Liassic flora but also of value in the palaeobiogeography of the Tethys area in Lower Jurassic times.

ABSTRACT Jurassic northward migration of Mexico, which lay on the southern part of the North America plate, resulted in temporal evolution of climate-sensitive depositional environments. Lower–Middle Jurassic rocks in central Mexico contain a record of warm-humid conditions, indicated by coal, plant fossils, and compositionally mature sandstone deposited in continental environments. Paleomagnetic data for central Oaxaca and other regions of central and eastern Mexico indicate that Lower and Middle Jurassic rocks were deposited at near-equatorial paleolatitudes. In the Late Jurassic, the Gulf of Mexico formed as a subsidiary basin of the Atlantic Ocean when the Pangea supercontinent ruptured. Upper Jurassic strata across Mexico, including eolianite and widespread evaporite deposits, indicate dry-arid conditions. Available paleomagnetic data (compaction-corrected) from southern and northeast Mexico for Upper Jurassic strata indicate deposition at ~15°N–20°N. As North America moved northward during Jurassic opening of the Atlantic Ocean, different latitudinal regions experienced coeval Middle–Late Jurassic climatic shifts. Climate transitions have been widely recognized in the Colorado Plateau region. The plateau left the horse latitudes in the late Middle Jurassic to reach temperate humid climates at ~40°N in the latest Jurassic. Affected by the same northward drift, the southern end of the North America plate represented by central Mexico gradually reached the arid horse latitudes in the late Middle Jurassic as the Colorado Plateau was leaving them. As a result, Late Jurassic epeiric platforms developed in the circum–Gulf of Mexico region after a long period of margin extension and were surrounded by arid land masses. We propose that hydrocarbon source-rock deposition was facilitated by arid conditions and wind-induced coastal upwelling.