【摘要】 <正> 本文所描述的标本是北京大学地质地理系湘西区测大队,于1959—1961年间在湖南资水流域采集的。资水流域的奥陶纪笔石地层相当发育。首先在1933年,由田奇(?)、王晓青、许原道等所发现,命名为桥亭子系。1949年,王超翔、边效曾在安化烟溪采到很多笔石,改名为烟溪板岩。据穆恩之的意见,其时代应属早奥陶世的兰瓦恩期。1959年,湖南省地质局和北京地质学院的工作队,在湖南祁东“龙山系”中采到Dicellograptus sextansvar.exilis,Elles et Wood,证明有中奥陶统的存在。1960年,北京大学湘西区测大队于安化矛园、烟溪及新化炉关三个剖面中,均采到了上、中、下奥陶统的笔石化石,证明资水流域有中、上奥陶统的存在。最近,金玉琴对安化烟溪奥陶纪地层作进一步的研究,采到了更多还原

【Abstract】 The graptolites here described were collected from the Tzishui Valley of Hunan bythe Regional Geological Surveying Party of western Hunan under the auspices of theDepartment of Geology and Geography,Peking University during the field seasons of1959—61.Formerly only strata of lower Ordovician age were known in this area,butup to the present more and more reports have ascertained that there not only lower Or-dovician,but also middle and upper Ordovician have been found.However,whetherthe existence of upper middle Ordovician and lower upper Ordovician is still in doubt.During the summer of 1963,rich fossils were again collected by the writer and fivestudents of the university in the Lu-Guan-zhen area of Xin-Hua in central Hu-nan.The graptolites obtained by them include Pleurograptus,Dicellograptus,andClimacograptus etc.,obviously belonging to early upper Ordovician,while other graptolitessuch as Dicranograptus,Dicellograptus,and Climacograptus,together with the trilobiteCyclopyge and fragments of cephalopods,brachiopods,etc.,undoubtedly indicate the latemiddle Ordovician.Therefore these two horizons may be favorably compared with theCaradocian of England.Such graptolite-bearing strata so completely developed fromlower Ordovician to upper Ordovician like in this area are rarely met with in China.Accordingly this area may play an important role in subdivision,zonation and correla-tion of the Ordovician stratigraphy.First of all only lower Ordovician scandent Axono-lipa are described in the present paper including four genera and eight species.Amongthem one species and one subspecies are new.The new species,Paracardiograptus abnormis is worthy of mention.As compared with the specimen of “thin-film type”it is similar to Glossograptus crudus Harris et Thomasof Australia,but with that of “low-relief type”it is similar to Paracardiograptus.Thusit is thought that Glossograptus crudus of Australia might be referred to the genus Para-cardiograptus.On the other hand it is also similar to Glyptograptus sinodentatus Muet Lee.The rigid nema of this new species always extends out from the rhabdosome.This character signifies probably that it is related to Axonophora.更多还原