【摘要】 本文报道河北平泉九佛堂组及北京坨里群辛庄组、芦尚坟组早白垩世的植物化石共12种,包括一个新种。其中小叶型的卤叶蕨 Acrostichopteris 和莱尼苏铁杉 Podozamites reinii 在我国为首次发现,它们对确定地区时代颇具意义。对伸长似金粉蕨 Onychiopsis elongata 的实羽片形态与现代金粉蕨 Onychium 作了比较。与邻近辽西及东北其它地区早白垩世植物群对比,归入北方温带植物区。更多还原

【Abstract】 The present paper describes the fossil plants found from Pingquan district,northern Hebei and Beijing.Those were collected from the Jiufotang formation of Pingquan include the following species:Acanthopteris gothani Sze,Acrostichopteris pingquan- ensis sp.nov.,Acrostichopteris sp.,Cladophlebis serrulata Samylina,Cladophlebis sp., Neozamites denticulatus(Kry.et Pry.)Vachrameev,Baiera gracilis Bunbury,whereas those were obtained from the Xinzhuang formation and Lushangfen formation of Tuoli group of Beijing are Coniopteris bur ejensis(Zalessky)Seward,Onychiopsis elongata(Geyler)Yokoyama,Acrostichopteris sp.,Ginkgo sibirica Heer and Podoza- mites reinii Geyler.Thus,these formation(Jiufotang,Xinzhuang and Lushangfen) are believed to be of Early Cretaceous age. The new species is described as follows: Acrostichopteris pingquanensis sp.nov. Description penultimate pin nae as a whole widely linear,very long,up to 10 cm, 3.5 cm wide;principal rachis comparatively stout,1.5 mm broad and with one longi- tudinal ridge.Pinnae arranged almost sub oppositely,contiguous,narrowly lanceolate, very short,up to 1.5—2 cm long and 3—4 mm wide;rachis slender,indistinct,with about 6 pinnules on each side,anadromic branching,alternate;pinnule minute,nar- rowly cuneate,and decurrcnt.Generally,the upper basal pinnules divided into un- equal lobes,the adaxial one of which in turn cut once or twice into segments.Whose apexes are obtuse or truncate,with short teeth. Upper pinnules often larger than the lower ones;the upper primary pinnule arising almost parallel to the principal rachis,where as the lower pinnules forming small angle with the rachis and pointing forward,leaving a space occupied by two pinnules of the next pinna. Nerves slender,flabellately diverging and forking dichotomously,about 5 times and the ultimate branches extending into the segments and teeth.更多还原