In the south-central Andes, several researchers have documented series of numerical terms that some have attributed to a hitherto unknown language: Lengua X. Indeed, they are difficult to link, as a whole, with numerical series from the known languages of the area. This paper discusses the available information on these series and attempts to trace their origin. It is difficult to argue that they are the remnants of a single, vanished language. Instead, it is argued that Lengua X numbers for ‘one’ and ‘two’ originate in Aymara, a language from the highlands, whereas terms for ‘three’ to ‘five’ originate in Mosetén, a language from the eastern foothills. Additional parallels with Uru-Chipayan, Quechua, and Aymara (terms from ‘six’ to ‘ten’) suggest that Lengua X numbers reflect a unique and complex situation of language contact in the south-central Andes.

中文翻译：

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Lengua X：安第斯之谜

在安第斯山脉中南部，一些研究人员记录了一系列数字术语，有些人将这些术语归于一种迄今未知的语言：Lengua X。实际上，它们整体上很难与该地区已知语言的数字序列联系起来. 本文讨论了有关这些系列的可用信息，并试图追溯它们的起源。很难说它们是单一的、消失的语言的残余。相反，有人认为“一”和“二”的 Lengua X 数字起源于艾马拉，一种来自高地的语言，而“三”到“五”的术语起源于莫塞滕，一种来自东部山麓的语言。与乌鲁-奇帕扬、克丘亚语的其他相似之处，