北祁连走廊区早中石炭世网状脉之蕨类的发现及意义

DISCOVERY OF FERNS WITH RETICULATE VEINS IN EARLY—MIDDLE CARBONIFEROUS FROM NORTH QILIAN ZOULANG AREA, GANSU PROVINCE AND THEIR SIGNIFICANCE

报道了甘肃北祁连走廊区早中石炭世的沉积特征。该地层中发现的大量具网状脉的蕨类化石，计有网羊齿１３ 种、矛羊齿２ 种和杂羊齿１ 种。并对其中的Ｌｉｎｏｐｔｅｒｉｓ ｍ ｕｓｔｅｒｉｉ、Ｌ．ｏｂｌｉｑｕａ、Ｌ．ｐｓｅｕｄｏｎｅｕ－ｒｏｐｔｅｒｏｉｄｅｓｓｐ． ｎｏｖ．、Ｌ．ｏｖａｌｉｓｓｐ． ｎｏｖ．、Ｌ．ｌａｎｃｅｏｌａｔｕｓｓｐ．ｎｏｖ．、Ｌ．ｖａｒｉｕｍ ｓｐ． ｎｏｖ．、Ｌｏｎｃｈｏｐｔｅｒｉｓｌａｎｃｅｏｌａｔｕｓｓｐ． ｎｏｖ．、Ｌ． ｃｒａｓｓｉｎｅｒｖｉｓｓｐ． ｎｏｖ．和Ｐａｌａｅｏｗ ｅｉｃｈｓｅｌｉａ ｙｕａｎｉｉ等９ 种进行了描述。这一地区早中石炭世植物区似应属欧美植物区，但欧美植物区系的某些重要分子在我国这一地区的出现，要比欧美和前苏联更来得早一些，这对前人关于上述构成欧美植物区系的３ 个具网状脉蕨类的主要属起源于西欧或前苏联的看法提出了异议。并进一步提出，我国的华夏植物群不应从欧美植物区划出，而是继我国西北地区具地方色彩的晚泥盆纪植物群后发展起来的。

The sedimental characteristics of Early—Middle Carboniferous from North Qilian Zoulang area, Gansu province and some fossil ferns with reticulate veins found in the sediments were described in details. They were: Linopteris msterii, L. obliqua, L. pseudoneuropteroides sp.nov., L. lanceolatus sp. nov., L. ovalis sp. nov., L. varium sp. nov., Lonchopteris lanceolatus sp. nov., L. crassinervis sp. nov. and Palaeoweichselia yuanii. The flora which was found in Early Middle Carboniferous from North Qilian Zoulang area, Gansu province belongs to the Euramerica flora. But some important elements of the flora appeared in China earlier than in Euramerica and Pre USSR. By the way, the author thinks, Cathaysian flora came from north west part of China, North Qilian Zoulang area were path of Cathaysian flora.