First Discovery of the Earliest Angiospermous Megafossils in the World

The first discovery of the earliest angiospermous megafossils, so far in the world,was made by the authors from the Lower Cretaceous Chengzihe Formation of Jixi Basin, eastern Heilongjiang Province,China.Among the angiospermous fossils there are 5 species belonging to 5 genera (including 4 gen.et sp.nov.) reported in this paper.Their microphyllous leaves with irregular venations show the characteristics of some primitive angiosperms whose age is mostly corresponding to the late Hauterivian-early Barremian, partly proved by the underlying conformably marine beds with the Valanginian-Hauterivian dinoflagellates revealed newly also by the authors.     

关于一个组合学问题的显式解

这里讨论了关于钟开莱的一个组合学问题的两种不同形式的显式解,并指出了需要进一步研究的问题。     

世界最早的被子植物化石群的首次发现

本文首次报道了世界最早的被子植物大化石群在我国黑龙江省鸡西盆地早白垩世城子河组的重要发现。首批报道的5属5种(包括4个新属、种)均为具网状脉系的双子叶植物。文中还讨论了这一发现对研究被子植物起源与早期演化、全球性早白垩世生物地层对比及古地理、古气候恢复等方面的重要意义。