The following hypothesis is proposed: that the distribution in time and space of Desert culture(s) and Hokaltecan languages imply a connection, that at one time there was a continuous band of Hokaltecan people practicing Desert culture from the Great Basin to the Texas and Tamaulipecan coasts, that this continuity was disrupted by an incursion of Utaztecan highlanders moving along the cordillera into Mexico, that proto-Shoshoneans entered the Great Basin from the northeast, that the Yuman peoples are a remnant block and not a disrupting wedge of Mexican origin, and that some of the similarities between cultures in California, the American Southwest, and Mexico are survivals of the basic proto-Utaztecan or Macro-Penutian culture, while still others are the result of interchange through a relatively homogeneous cultural medium made up of Utaztecan highlanders living along the western cordillera from central Mexico to the American Southwest.