that of Dr. Arber (1917) for New Zealand. To the former is due the Triassic and Jurassic maps here given (with minor modifications). Extensive fresh-water deposits formed in the neighbourhood of Sydney, comprising the extensive conglomerates, shales, and sandstones of the Narrabeen and Hawkesbury series, of probably early and middle Triassic age. The basin of deposition probably discharged into a northward-extending gulf ancestral to the Tasman Sea. In Rhaetic times the area of sedimentation increased. A second basin formed in south-eastern Queensland (the Ipswich series), and another, probably in Tasmania, discharging into the same gulf, which seemed to have reached a maximum extension at this time, for the deposition of the Rhaetic lacustrine Wianamatta shales above the Hawkesbury sandstone was interrupted near its close by a brief incursion of the sea passing from this gulf as far westwards as the Blue Mountains. Here it deposited an argillaceous limestone containing a small group of ostracods and foraminifera, “a brackish or estuarine fauna having a curious intermingling of Rhaetic and Lower Jurassic types with others more properly referable to the Upper Palaeozoic of Europe” (Chapman, 1909).* It is perhaps more than a coincidence that the time-range of the foraminifera should thus be analogous with that suggested by the fish-fossils in the Wainamatta series (Woodward, 1908). It is interesting to note the close approximation in time between this temporary ingression of the sea into eastern Australia and its regression from New Caledonia. Jurassic. The Jurassic period witnessed a wider extension of these lacustrine deposits. Walkom (1918) shows them as stretching from the Cape Yorke Peninsula southwards and to the northern parts of South Australia and of New South Wales. He is of the opinion that this basin discharged into the sea by some outlet to the north, and was not connected with a south-eastern sea by a Queensland Gulf such as Neumayr had supposed. A second basin is that comprising the Jurassic coalfields of Victoria and eastern Tasmania, which Walkom thinks may have drained into the Southern Ocean. The intervening region of the present Tasman Sea, hc considers, was probably for the most part a land area, the coast of which lay east of New Caledonia (which was land till near the close of Jurassic times), but west of New Zealand, which formed the littoral zone across which the strand fluctuated (until the early part of Cretaceous time), producing intercalated marine and fresh-water deposits, the latter predominating in the latter part of the period. The comparison of the work of Walkom on the Australian flora, and of Arber on that of New Zealand, briefly summarized by the writer (Benson, 1919), indicates a very general similarity, though with comparatively few forms common to the two regions. In general, also, the Australian Mesozoic flora contains four times as many species as that of New Zealand, perhaps due to the unfavourable littoral habitat of the latter, and the modifications which have ensued during their migration back and forth with the fluctuation of the coast-line. The general conditions indicated continued until the commencement of the Cretaceous period, the highest plant-beds in this series in New Zealand being those of Waikato Heads, which Arber considers of Neocomian age; in these, associated with Cladophlebis and Taeniopteris, appear angiospermous leaves (Artocarpidium), which seem to be more related to the figs than to any other modern plants. Of about the same age as these are the much larger floras described by Walkom (1919) from the Burrum and