Two long series of samples from Tikal, Petén, Guatemala, have been dated by the radiocarbon method for the purpose of limiting the range of possible correlations of the Maya calendar with the Christian. These samples from lintel and vault beams were selected from latest-growth portions of the beams which were presumably cut at times corresponding to Maya dates carved on lintels of two temples. Christian dates for dedicatory Maya dates of the lintels are calculated according to five correlation hypotheses, and are compared with radiocarbon dates for ten beams from Temple IV and six from Temple I. These new radiocarbon dates are shown to be closely related to “absolute” ages by means of radiocarbon counts of tree-ring-dated samples of the same period. The radiocarbon results support the 11-16 (Goodman-Thompson-Martinez) correlation. Attention is given to previous radiocarbon tests by other laboratories of beams removed from Tikal many years ago which seemed to favor the 12-9 correlation in Spinden or Makemson variants. With the aid of new radiocarbon dates for similar samples, reasons for the differences in results are discussed.

A series of large structures termed great kivas has been excavated at Point of Pines, Arizona. To add to the sequence of these kivas a site was excavated in 1959 on one of the upper tributaries of Eagle Creek, 16 miles northeast of Point of Pines. The site complex included a great kiva and five attached rooms, a U-shaped masonry pueblo, scattered storage units, trash deposits, a reservoir, and agricultural terraces. The kiva was rectangular with an encircling bench, a stepped entrance, two possible floor resonators, and a post pattern suggesting a polygonal roof support. The ceramic content of the site places it late in the Reserve phase which is dated from A.D. 1000 to 1150.

This particular kiva type appeared during late Three Circle phase and had a distribution centered in the upper San Francisco and Blue River valleys. The antecedents for the structure seem to lie in the general Mogollon great kiva tradition. The surrounding areas were examined for possible contributions to the complex; ceramic evidence of contact was present but no definite source for the introduction was found. The presence of a number of Anasazi traits plus the direction of Reserve phase cultural change suggests a northern source for this kiva form.

The foot-turned parador or mobile pottery support used at Acatlán is very similar to the kabal used at the Maya village of Mama, Yucatán. It is viewed as an extension of the Maya kabal technique into the mold-technique area of central Mexico. It is suggested that the principle of the Maya kabal and its Acatlán counterpart may have been known and used by the Olmec of La Venta. Several vessels from La Venta which resemble the Mama type of kabal offer evidence for the possible antiquity of the kabal-parador technique of pottery making.

Shifting cultivation, which is the technique commonly followed by tropical agriculturists, while wasteful of land use in requiring a long fallowing period, will support variable population densities depending upon crops grown, farming tools used, and soil fertility. Twenty persons per square kilometer is accepted as the density for the region around the Preclassic La Venta site which was begun about 800 B.C. and abandoned about 400 B.C. The occupation area of the La Venta culture group is believed to lie between the Coatzacoalcos and Tonalá rivers and amounts to about 900 square kilometers, thus yielding a population figure of about 18,000, of which 3600 are family heads. The total man-days of labor required to build the La Venta site is estimated to be 1,100,000, and the four major rebuildings of the site features are suggested as having been done at completion of 52 and 104 year calendar rounds.

Eden and Scottsbluff points and Cody knives were found in situ in a sand deposit with an estimated geological age of 10,000 to 7000 years. Numerous other Cody complex artifacts from the surface of the site are described. Fragmentary remains of a mammoth in a marl bed are stratigraphically older than the Cody artifacts.

Artifacts related to the Cody complex occur in medium-grained sand that is spread as a blanket eolian deposit a few feet thick in the Claypool site area, Washington County, Colorado. The artifact-bearing sand lacks noticeable dunal topography and lies unconformably on marl of Yarmouth age and on waterlaid coarse sand and fine gravel of Kansan age that underlie the marl. The deposits underlying the artifact-bearing sand are much too old to date the artifacts precisely, but the physical characteristics of the artifact-bearing sand suggest that it was deposited under conditions cool and dry, rather than warm and dry, possibly during retreat of Valders ice that began about 10,000 years ago. A moderately mature Brown Soil about 5 feet thick developed on the sand, possibly about 7000 to 5000 years ago during a moist phase of the Thermal Maximum. Thus, the artifacts are possibly 10,000 to 7000 years old. Deposits which overlie the artifact-bearing sand reflect several episodes of erosion and sedimentation that are inferred to represent climatic changes.

The mound near Gila Bend, western Arizona, excavated between November, 1958, and February, 1959 for the National Park Service by the Arizona State Museum, was rebuilt, modified, and repaired through six major stages of construction. The platform mound in use at any given stage was flat-topped and slope-sided with rounded corners and an irregular squarish or subrectangular outline. The platforms were made of a caliche plaster, and the sides were faced with a plaster of mixed caliche and adobe, placed directly over the earth core. Evidence of pre-mound occupation was encountered underneath the platform mound and in an excavated pit structure near the southeast corner of the mound. The entire historical sequence revealed by this excavation took place within the Sacaton phase of the Hohokam culture which may have lasted from A.D. 900 or 950 to A.D. 1100 or 1150 in the Gila Bend area. The significance of this Hohokam mound complex is that it represents a northern extension of the Mexican pyramid idea.

In a rejoinder to Taylor's review of his Tamaulipas monograph, MacNeish restated his method of analysis and reviewed the system he used to establish his phase sequence. Taylor claims that MacNeish has defended his position by introducing new data and by presenting a point of view not expressed in the original monograph. Taylor insists that MacNeish's reply only confirms his original criticism that the Tamaulipas sequence is built on the premise that one excavation unit equals one phase.

The original guess dates for Jarmo were about 6000 B.C. (and thus close to the recent Washington and Heidelberg radiocarbon dates of 6750 B.C.) rather than about 4750 B.C. (the date derived from Libby's original radiocarbon determinations) as suggested in the papers on obsidian dating in American Antiquity, Volume 25, Number 1.

A cross section of the surviving traces of two large prehistoric canals near Pueblo Grande, Phoenix, shows one to have originally been V-shaped in profile, about 6 m. wide and 4 m. deep, and the other U-shaped in profile, about 10 m. wide and 3 m. deep. Both were dug into coarse gravel and the broader (north) canal had been lined with brown clay subsequent to its construction and initial period of use. There is a possibility that the V-shaped South Canal was built first and perhaps abandoned when the North Canal was built. Both canals show evidence of repeated filling and clearing out, either by natural erosion due to a periodically swifter current or by the efforts of the Indians using the canals. Sherds under the banks and in the canals were too few for conclusive dating of construction and use, but suggest that this took place during the Soho phase of the Hohokam Classic period, that is, during the late 12th and the 13th centuries. Hohokam canals much older than this are known, and the occupation of nearby Pueblo Grande began earlier and lasted later than the Soho phase.

This cave in the Sierra Madre Occidental was excavated to obtain information from a little-known region which might help clarify problems of Mexican-Southwestern contacts. The excavation produced ten burials with associated mats and blankets, only a few artifacts, and both cultivated and gathered plant remains. Stylistic elements of Mogollon and Casas Grandes pottery and the cultivated plants suggest a beginning date of A.D. 1000; the lack of European artifacts, a terminal date of 1600. The death complex is interpreted by analogy with modern Tarahumara practices. The use of the cave is described in terms of a series of events and episodal analysis is presented as a way of operationalizing the conjunctive approach.

The 32 specimens from Waterfall Cave include apocynum-fiber textiles, cane and palm-frond matting and braids, a yucca-fiber leader on a fishhook, and a girdle or string apron. The matting is twilled; the textiles are plain weave and generally warp face. Technical aspects of these specimens are similar to those of textiles from Chihuahua published by Lila O'Neale in 1948. Pattern weaving is the only major new element found at Waterfall Cave.

Cultivated plants from Waterfall Cave include several varieties of maize, common beans, bottle gourd, and squash. Most of the corn is of the Pima-Papago race, and the whole plant complex is similar to the group of cultivated plants recently grown by the Papago and other Indians of southwestern Arizona and northwestern Mexico.

A textile recently found undoubtedly relates to an early phase of the Paracas style of the Peruvian south coast. The decorative techniques consist of slit tapestry, brocade, and warp striping. The tapestry design is a complex feline figure with various traits of the Chavin style. The techniques and design are of considerable interest since no Paracas textile of this or earlier date has been previously published.

A small rectangular house floor at the Gresham site, north of Kansas City is assigned on the basis of associated artifacts to the Steed-Kisker focus of Middle Mississippi. The house differs architecturally from the house at the Steed-Kisker site described by Wedel. These differences and other evidence point to the possibility of major cultural transitions in the area during Middle Mississippi time.

Maximum glaciation in eastern Siberia, the final glaciation, the mountainous area, and the land area exposed by moderate lowerings of sea level are plotted on a map to illustrate that two routes from northeast Asia to northwest North America were available for human movements. The southern route along the coastal shelf may have played a more significant role in the initial settlement of the New World than did the northern route along the Arctic shore.

Artifacts of Archaic types, human bones, and a partly burned log have been recovered from three layers of sediments on the floor of a shallow limestone cave now under water. The skeletal remains include a skull from Layer 2 with naturally preserved portions of brain inside. The charred log from Layer 3 produced a radiocarbon date of 8000 B.C. ± 200 years. The age of the preserved brain may not be as great as that of the log and human remains in Layer 3. The radiocarbon date is the earliest known date for man in Florida and suggests that during the early Southeastern Archaic, man lived in limestone caves in Florida when the sea level was considerably lower than at present.