我国某些苏铁类生殖器官化石的发现兼论苏铁类起源

本文对苏铁类化石的系统分类作了概要的介绍。重点报道了笔者在近廿年来所采集的苏铁类生殖器官化石，特别是中晚石炭世的一枚苏铁大孢子叶化石的发现，将苏铁类起源的时间大大地推前了，并指出其起源地应在中国西北的甘肃地区。所有这些生殖器官的发现将推动苏铁化石生殖生物学的发展，对其起源、分布、演化和苏铁植物区系的形成和发展提供了极为重要的材料。

DISCOVERIES OF SOME REPRODUCTIVE ORGAN FOSSILS OF CYCADS IN CHINA AND ON THE ORIGIN OF CYCADS

This paper reports reproductive organ fossils of cycads collected by the author in China.Male cone of cycads-Androstrobus pagodiformis Hsu et HU was discovered in 1976 from late Trias-sic Baoding coalfilds,Panzhihua,Schichuarg China. In the same horizon specimen Nilssonia and the seed of cycads are well-preserved.In the past Androstrobus had never been discovered in China. Theregore its significance is very importened.Cycadolepis sp. was collected from late Triassic Yanan, Schichuang. Primocycas chinensis Zhu et Du was collected by the author and Zhu Jia-nan et al in 1976 from the Early Permian,i.e. the Lower Shihhotse Formation , Dongshan,Taiyuan,Shanxi,Cycadeoidispermum petidatum Hu et Zhu and Dioonocarpus ovatus Hu et Zhu were collected from the Late Permian i.e.the Upper Shihhotse Formation,Dongshan,Taiyuan,Shanxi.Author mainly reports the first discovery of a macrobract of cycads from Middle-Late Car-bonifeurous, East part of Ganshu province. All these discoveries will develop the theory on the origin, the distribution,and the evolution of cycads.