关键词: 直立人;中更新世早期;郧县

Abstract: Skulls EV9001 and EV9002 were found in 1989 and 1990 respectively in the light brown sandy clay associated with mammalian fossils which include at least 18 species belonging to the South China fauna (Table 1). This site is dated as the early stage of Middle Pleistocene or even earlier.
Skull EV9001 (Plate I)
The vault is low. The brow ridges are thick. The supra-toral groove is shallow and wide. No obvious mid-sagittal ridge exists. Remnant of metopic suture can be seen. The orbits are quadrangular with rounded corners. The antero- lateral surface of the frontal process of the rygomatic bone faces forward. The anterior surface of the rygomatic process of the manilla is flat and faces forward, its lower margin starts from the maxillary body at a high position above the interalveolar septum between first and second molars. This margin extends horizontally lateralward then turns backward. The reconstructed pyriform orifice is low and wide. On the left side, the superior temporal line is distinct, the inferior temporal line is indistinct. The reconstructed zygomatic arch is lower than the Frankfurt Plane. The external auditory orifice is elliptical. The nasion is much indented. The post-orbital constriction is obvious. The condition of the sutures indicates this skull belonging to a middle-aged individual. The occipital torus exists. The foramen magnum is about 32.Smm long and 29.2mm wide. The remnant of the mastoid process shows that it is large and robust. The long axis of the tympanic plate forms a big angle with the sagittal plane of the skull. The mandibular fossae are deep (left, 11.0mm; right, 8.8mm). All 16 teeth are large and in situ, but are broken in different degrees. The upper incisors are vertically postioned. There is no prominent canine jugum.
Skull EV9002 (Plate II)
The brow ridges are robust. The medial segment of right brow ridge is 18. Imm thick. The supratoral groove is obvious. The remnant of metopic suture can be seen. The orbits are rectangular with rounded infero-lateral margin. The reconstructed pyriform orifice is narrower and higher than that of skull EV 9001. The starting point of the root of the zygomatic process of the maxilla is high. The canine fossa is shallow. A prominent canine jugum can be seen on right side. The incisors are vertically positioned. The sagittal circumference, frontal, parietal and occipital arcs are 350, 109, 112 and 129mm respectively. The occipital torus is well developed. The upper margin of the right temporal squama is convex. The parietal notch of the temporal bone is deep. The posterior branch of the zygomatic process of the temporal bone extends upward and backward and continues with the supramastoid ridge. The external auditory orifice is elliptical. It is 17.2mm medial to auriculare at left side. The mastoid process is robust. A weak eminence at the infero-posterior conrner of the parietal bone looks like an angular torus. The vault is well constricted behind the orbits. Judging from the condition of the sutures this skull represents a middle-aged individual. The parietal tuberosities are obvious. The occipital torus is well developed. The central protion of it is thicker than its lateral segments which are not continuous with the supramastoid ridges. The occipital plane connects with the nuchal plane with an angular turn. The former is obviously shorter than the latter. They are 47 and 67mm in length respectively. There is a short supratoral sulcus. The foramen magnum is 34mm long and 36.2mm wide. The mastoid process is robust. The mastoid notch is shallow and wide. The depth and sagittal diameter of left mandibular fossa are 6.5 and 21mm respectively; those for right side are 9.6 and 16.7 mm respectively. The post-glenoid process is low. No styloid process is found. The tympanic plate is thick. It forms a big angle with the sagittal plane of the skull than that in modern man. The palatal surface is uneven. The dental arch is close to parabolic in shape. The left third molar is small. M1 is much larger than M2.
Table 5 shows that the Quyuan River Mouth (Yunxian) skulls possess most of the common morphological characters shared by other Chinese fossil humans proposed by Wu(1990) and Wu and Zhang(1978). This fact indicates that Yunxian skulls constitute one of the important links in the human evolutionary lineage of China. Yunxian skulls have similarities and dissimilarities with those of Peking Man. Judging from the morphological features, associated fauna and cultural factors Yunxian skulls are probably closer to that of Lantian than to those from Zhoukoudian.
The morphological features of Yunzian skulls are concordant with those of Chinese fossils. This is resulted from regional continuous evolution of humans. Yunxian has some features similar to those found in Africa and Europe. This is due to the gene flow between China and those continents.

Key words: Homo erectus; Early Middle Pleistocene; Yunxian