Abstract: Seven hundred and thirty-seven specimens of grey marmots (Marmot baibacina) were collected in the western part of Boluokeru Mountain, a branch of Tianshan, from June to August, 1983.The worn degrees on the grinding dental surfaces of grey marmots were studied. And 12 age-groups were identified among the marmots, according to the varied worn degrees. They are as follows:I . Teeth not well erupted;Ⅱ. Striped dentinal worn scars in the transverse mid-ridge of P²;Ⅲ. P₂ and M³ not wormⅣ. Lunate enamel worn scars in P2 and M³ protocone;Ⅴ. "T" shaped dentinal scars in M³ protocone;Ⅵ. M³ protocone connects with middle and posterior transverse ridge, forming "⊂ " shaped dentinal scar;Ⅶ. M³ protocone connects with anterior,middle and posterior transverse ridge, forming "E" shaped dentinal scanⅧ. The enamel of protocone surfaces of various molar teeth is worn into raised thin edge, with external teeth depressed)Ⅸ. The thin enamel edges of various molar teeth and tooth rings are worn off;Ⅹ. M¹ shows a "spoon" shape;Ⅺ. M¹ and M² show "spoon" shapes;Ⅻ, M³ surface shows five-petaled shapes along the gum.

Key words: Gray marmot, Marmota baibacina, Age, Molar worn degree

摘要： 有关灰旱獭Marmota baibacina的年龄鉴定,等(1973)曾以臼齿磨损度作过描述,并划分出6个年龄组,但缺少年龄与个体发育关系的资料。国内以牙齿磨损度鉴定灰旱獭年龄与种群年龄组成尚未见报道。 灰旱獭为天山山地的优势鼠种,分布广,数量多,既是自然疫源性疾病的宿主动物,又是重要的毛皮兽。我们于1983年6—8月对该旱獭的年龄鉴定方法及其年龄组成进行了研究,现将结果报道如下。

关键词: 灰旱獭, 年龄, 臼齿磨损度