Leaves in Autumn

1908 Botanical Gazette  
i908] CURRENT LITERATURE 239 group from Greenland to Patagonia in the western hemisphere and from Spitzbergen to Cape Colony in the eastern is to be contrasted with its present occurrence in South America and the Australasian region. This means that araucarians have disappeared from North America, Europe, Africa, and practically all of Asia. Recent investigations in the Atlantic coastal plain show that the group not merely occurred in that region during the Mesozoic, but was abundant, perhaps
more » ... abundant, perhaps the most abundant coniferous type of the older Mesozoic. From this region BERRY describes three new species: Araucarites Zeilleri, from New Jersey; Araucaria bladenensis, from North Carolina to Alabama; and Araucaria Jeffreyi, from North Carolina.-J. M. C. Embryo sac and embryo of Urticaceae.-MODILEWSKYI5 has examined twelve genera of Urticaceae (Urtica, Elatostema, Laportea, Urera, Parietaria, Fleurya, Boehmeria, Dorstenia, Morus, Celtis, Cannabis, and Humulus), and finds that the embryo sac and embryo are in general of the ordinary dicotyledonous type. Elatostema sessile, Dorstenia drakeana, and D. contrayerva are said to be parthenogenetic, and Celtis occidentalis is chalazogamic. In the species of Dorstenia and in Urtica cannabina the antipodals multiply, but finally disappear. The polar nuclei fuse very early, and in Elatostema endosperm formation occurs without polar fusion. In Urtica cannabina a conspicuous antipodal haustorium is developed, and a much smaller one appears in U. urens. Many other details are recorded, but they are of no special significance.-J. M. C. I5 MODILEWSKY, JAKOB, Zur Samenentwicklung einigen Urticifloren. Flora 98: 423-470. figs. 71. i908. i6 REDDICK, DONALD, and WILSON, C. S., The black rot of the grape, and its control. Cornell Univ. Agric. Exp. Sta., Bull. 253:367-388. April i908. I7 TSWETT, M., Ueber die Verfarbung und die Entleerung des absterbenden Laubes. Ber. Deutsch. Bot. Gesells. 26a:88-93. i908.
doi:10.1086/329714 fatcat:kpste45vsnarjkuwhpq5udxqqe