Ruppert discovered some but not all stones from sculptured panels in the debris of the north and south sides of the temple (1931:123). The panels were most likely positioned in the north and south walls in the medial zone of the lower facade. He also recovered pieces of mask panels, but never more than about half of the stones for any mask. The building is named for the sculptured panels located on the north and south exterior walls of the colonnade (Ruppert 1931:Pl. 11).

have a concavity at the rear to allow them to fit against the bases of the round columns of the temple. Serpent columns in the other major buildings at the site, when the columns were round, were constructed with the head and lower column drum carved from a single block of stone (Upper Jaguars, Castillo, Chac Mool, Big Tables), while heads and basal columns were separate if the column shaft was rectangular (Warriors, High Priest’s Grave, Little Tables). The design of the serpent heads from the Temple of the Wall Panels was a third variety, of unknown chronological significance, but sometimes considered late among the serpent columns. Some slight support for this view comes from structure 3E5, a small building on the southeast side of the Court of the Columns, where a similar type of head and column arrangement was probably used (Ruppert 1952:85). This building, because of its peripheral position on the Court of the Columns, probably falls in the latter half of the architectural sequence of the site.

Two periods of architectural activity are evident from the excavation of the Temple of the Wall Panels. Initially, a stairway at the rear of the colonnade gave entrance to the upper temple, similar to the access to the Temple of the Warriors through the rear of the Northwest Colonnade. Sometime later architects walled up this entryway and added a new stairway to the front of the colonnade to allow access to the temple (Ruppert 1931: 133-134). First, builders encased the central two columns of the four of the west facade of the colonnade in masonry piers, then they enclosed the piers with a wall, and lastly they constructed the stairway. Finally, they added flanking ramps to the stairway, and moved the serpent heads, which had rested against the two columns of the temple, to the bases of these stairway ramps (Ruppert 1931:134-136, Fig. 2, Pls. 2, 3, 9a, 15).

In addition to secondary use of the serpent heads at the bases of the stairway ramps, at least one of the serpent tails was carved from what had been a hieroglyphic lintel, and Ruppert reported that 15 glyph blocks could still be recognized, although the glyphs themselves are obliterated (1931:124). Another example of a reused sculptured stone in the construction is the inverted column drum carved with two atlantean Figures found in situ in the southeastern column of the colonnade (Ruppert 1931:132). Since atlantean sculptures are only found in the Modified Florescent

There are few architectural clues to the general chronological position of this structure. The serpent heads are unique among those in the major buildings of Chichén Itzá, for they

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