he
village grew, each added row facing toward the back of an older row,
producing a series of courts, which, to the present time, show more
terracing on their western sides. The eastern side of each court is
formed, apparently, by a few additions of low rooms to what was
originally an unbroken exterior wall, and which is still clearly
traceable through these added rooms. Such an exterior wall is
illustrated in Pl. XVIII. This process continued until the last cluster
nearly filled the available site and a wing was thrown out corresponding
to a tongue or spur of the knoll upon which it was built. Naturally the
westernmost or newer portions show more clearly the evidence of
additions and changes, but such evidence is not wholly wanting in the
older portions. The large row that bounds the original eastern court on
the west side may be seen on the plan to be of unusual width, having the
largest number of rooms that form a terrace with western aspect; yet the
nearly straight line once defining the original back wall of the court
inclosing cluster on this side has not been obscured to any great extent
by the later additions (Pl. XXVIII). This village furnishes the most
striking example in the whole group of the manner in which a pueblo was
gradually enlarged as increasing population demanded more space. Such
additions were often carried out on a definite plan, although the
results in Tusayan fall far short of the symmetry that characterizes
many ruined pueblos in New Mexico and Arizona.

[Illustration: Fig. 11. Diagram showing growth of Mashongnavi.]

[Illustration: Fig. 12. Diagram showing growth of Mashongnavi.]

[Illustration: Plate XXIX. West side of a principal row in
Mashongnavi.]

A few of these ancient examples, especially some of the smaller ruins of
the Chaco group, are so symmetrical in their arrangement that they seem
to be the result of a single effort to carry out a clearly fixed plan.
By far the largest number of pueblos, however, built among the southwest
tablelands, if occupied for any length of time, must have been subject
to irregular enlargement. In some ancient examples, such additions to
the first plan undoubtedly took place without marring the general
symmetry. This was the case at Pueblo Bonito, on the Chaco, where the
symmetrical and even curve of the exterior defensive wall, which was at
least four stories high, remained unbroken, while the large inclosed
court was encroached upon by wings