中文摘要：

本文简述了马圈沟旧石器遗址产出的哺乳动物化石：出自马圈沟遗址Ⅲ的20个种,马圈沟遗址Ⅰ的4个种,半山遗址的7个种;分析了以Allophaiomys deucalion,Cromeromys gansunicus,Borsodia chinensis等小哺乳动物组合为代表的马圈沟遗址Ⅲ的生物地层时代为早更新世早期,绝对年龄应大于1.80Ma;讨论了该遗址生物地层时代与磁性地层年代的关系。

英文摘要：

The Majuangou section（= MJG,40°13′31.2″E,114°39′50.9″N） lies near Cenjiawan village and on the south of the Sanggan river in the Nihewan Basin.In 1990,Wei Qi first reported a new paleoliths-bearing layer from the middle part of the Majuangou section with the name Banshan Site（Wei Qi,1994）.Two years later,the Hebei Province Institute of Cultural Relic（=HPICR） found another artefact layer named as ＂Maguangou Site＂from the lower part of the same section and did excavation in the next year（Li and Xie,1998）.In 2001,the first two authors gathered numbers of mammal remains and several paleoliths by washing the matrix collected from the＂New artefact layer＂,8 meters below the bottom of ＂Maguangou Site＂（Cai and Li,2003）.A test excavation was done and Goudi Site was named by Wei Qi（Wei,2002）.During the HPICR′s excavation seasons from 2001 to 2005,the fourth artefact layer was found and called MJG Ⅱ.The four artifact layers found in the Majuangou section are,from the top to bottom,Banshan Site, MJGⅠ（=＂Majuangou Site＂in Li et al,1998）,MJG Ⅱ and MJG Ⅲ（=＂New artefact layer＂in Cai and Li,2003 and ＂Goudi Site＂ in Wei,2002）（see Fig.1）.Zhu et al（2004） reported magnetostratigraphic results of the four artefact layers mentioned above. The magnetic age of the MJG Ⅲ given by Zhu et al（2004） is about 1.66Ma,while the biostratigraphic age estimated by Cai et al（2003） is suggested to be older than 1.80Ma.There is a small disparity between the two results.In 2005,invited by HPICR,the authors undertook the screen-washing work in the Majuangou sites and collected additional fossil mammalian specimens from MJG Ⅰ and Banshan Site.The purpose of this paper is to briefly describe the fossil mammals collected in 2001 and 2005 and to ascertain the age of the fossil-bearing beds.Further more,the potential factors interfering with the determination of magnetic chronology for these layers are discussed. By the way of washing about 3.5 tons of matrix,553