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Among South American vigesimal systems, the best known is that of the Chibchas or Muyscas of the Bogota region, which was obtained at an early date by the missionaries who laboured among them.

This system is much less extensive than that of some of the more northern races; but it is as extensive as almost any other South American system with the exception of the Peruvian, which was, however, a pure decimal system.

As has already been stated, the native races of South America were, as a rule, exceedingly deficient in regard to the number sense.

Their scales are rude, and show great poverty, both in formation of numeral words and in the actual extent to which counting was carried.

If extended as far as 20, these scales are likely to become vigesimal, but many stop far short of that limit, and no inconsiderable number of them fail to reach even 5.