Pueblo architecture developed. If a low wall of masonry were used as a
support for rafters, in the manner shown in figure 237, and additional
space were sought by excavation, the form shown in the illustration
would be retained, for the construction would be seriously weakened if
the rude stonework were placed directly on the edge of the excavation.
Possibly this practice has some bearing on the Pueblo requirement that
the kivas should be at least partly excavated, a requirement still
rigidly adhered to. The conservatism of the Indian mind in matters
connected with their ceremonials is well known, and forms and practices
long abandoned in ordinary house construction still survive in the
building of the kivas.

[Illustration: Fig. 236--Section of a summer hut]

Plate LXXXVI shows a shelter somewhat resembling that last described,
but of more simple construction. Here the main crosspiece which forms
the front of the shelter is supported by forked upright timbers, as in
the previous example, and here also the fork of the main upright is too
large and has been filled in.

[Illustration: Fig. 237--Masonry support for rafters]

Aside from the types described, which illustrate the more common forms
of summer shelters, all kinds and degrees of variation are found. As
they, unlike the regular hogán, do not follow any rule or precedent,
their form depends largely on the facilities or the particular
requirements or abilities of the builder. Figure 238 shows a shelter in
the mountains, where timber is abundant. Except that it is not covered
with earth and has no door-frame, it might be classed as a regular
hogán.