held together in their village as a social unit, with a limited commerce. The range of trade indicated by the excavations and confirmed by Donna Maria reveals a narrow world, with a diameter of not much more than twenty miles. The two broken arrowheads from Napa and one broken basaltic lava mortar, whose material must have come from far to the northward, are unique importations to be explained by accident rather than by regular trade, since the other mortars are all made of bowlders easily found in the vicinity, and since, as I have said, the broken arrow points are unique. The hill tribes eastward essentially bounded their world. Tradition and evidence alike show them to be a spur of population entering the valley from the southward.
Fig. 7.
Contact with the more warlike and better equipped northern tribes would either have destroyed them or developed their own culture to a higher status of defense.
This low status of defense, the fact that their implements are so similar to the natural objects which suggest them, the low type of skull (Fig. 7), all go to show that the Indian of the Santa Clara Valley was one of the most primitive types known to ethnology within the historic era. The early fathers and voyagers have left a good deal of observation in regard to him, but all this observation is more or less vitiated by the fact that it was made after the contact of Spaniard and Indian had already begun its work. For this reason the evidence of the Robles Rancheria is especially valuable, since it apparently antedates this influence entirely and shows us primitive man in one of his most primitive seats. Nothing possessed or made by the men of the Robles Rancheria indi-
