iffers greatly in character from the
rest of the ruins. Here the rooms or inclosures are defined only by a
few stones on the surface of the ground and partly embedded in the soil.
There is no trace of the debris of fallen walls. These outlined
inclosures appear never to have been walled to any considerable height.
Within one of the rooms is a slab of stone, about which a few ceremonial
plume sticks have been set on end within recent times.

[Illustration: Plate XLI. Back of Oraibi house row.]

The motive that led to the occupation of this mesa was defense; the
cause that led to the selection of the particular site was facility for
procuring a water supply. The trail on the west side passes a spring
half way down the mesa. There was another spring close to the foot trail
on the south side; this, however, was lower, being almost at the foot of
the talus.

In addition to these water sources, the builders collected and stored
the drainage of the mesa summit near the southern gap or recess. At this
point are still seen the remains of two reservoirs or dams built of
heavy masonry. Only a few stones are now in place, but these indicate
unusually massive construction. Another reservoir occurs farther along
the mesa rim to the southeast, beyond the limits of the plan as given.
As may be seen from the plan (Pl. LX) the two reservoirs at the gap are
quite close together. These receptacles have been much filled up with
sediment. Pl. LXII gives a view of the principal or westernmost
reservoir as seen from the northeast. On the left are the large stones
once incorporated in the masonry of the dam. This masonry appears to
have originally extended around three-fourths of the circumference of
the reservoir. As at Ketchipauan, previously described, the upper
portion of the basins merged insensibly into the general drainage and
had no definite limit.

The Zuni claim to have here practiced a curious method of water storage.
They say that whenever there was snow on the ground the villagers would
turn out in force and roll up huge snowballs, which were finally
collected into these basins, the gradually melting snow furnishing a
considerable quantity of water. The desert environment has taught these
people to avail themselves of every expedient that could increase their
supply of water.

It is proper to state that in the illustrated plan of the Taaaiyalana
ruins the mesa margin was sketched in without the aid of instrumental
sights, a