in France had only just begun to address the question of the periodization of Quaternary human artifacts. Both édouard lartet’s chronology, based on fauna, and gabriel de mortillet’s, based on lithic types, were presented to the first meeting of the Congrès International d’Anthropologie et d’Archéologie Préhistoriques, which was held in Paris in 1867, the year in which Delgado published his results. In this theoretical context, therefore, the only question that made sense was whether the lower deposit (and the skull derived from it), now known to date to the Upper Paleolithic, could be considered of Quaternary age.

The criteria used at the time to assess such an antiquity were twofold: paleontological, or the secure association of human remains or artifacts with extinct faunas, and geological, or secure association with deposits indicative of an earth not yet “modern in form”—that is,association with the “extensive and general deposits of loam and gravel” for which william buckland coined the term diluvium. Later, after the abandonment of the equation between such deposits and the great deluge, loam and gravel deposits also became known as drift. Drift was unequivocally recognized as a distinctive stratigraphic unit, regardless of the debate that animated mid-nineteenth-century geology over whether it owed its genesis to flooding or glaciation. However, this unit was generally considered to be associated with the extinct faunas; hence “anterior to the [earth’s] surface assuming its present form” then meant both modification of the earth’s topography and faunal extinctions.

Since Delgado was unable to identify any representatives of clearly extinct species among the animal bones recovered in the lower deposit at Casa da Moura, he was obliged to resort mainly to geological arguments in order to try to establish its chronology. Noting that the matrix of this deposit was very similar to the diluvial sands that covered the surrounding plateau and filled its karstic fissures, he thought that the sediments in Casa da Moura had been derived from these surficial deposits and were therefore more recent. Yet they were older than the last geomorphological changes that had affected the area, since they contained no pottery. The fact that the absence of pottery could be used as an indicator of an earth “not yet modern in form” was demonstrated by the finding of shards in the lacustrine tuffs into which one of the small rivers of the plateau had cut its bed.

To complete his geological reasoning, Delgado also resorted to comparative analysis of the archaeological materials found in the lower deposit. In this context he noted that the primitive character of the artifacts and the absence of pottery indicated that they should predate the Danish kjokkenmoddings (kitchen middens). At the time, these were thought to be of late-Quaternary age. The resemblance of some of the flaked flints to similar materials reported by Carlos Ribeiro from diluvial deposits of the Tagus Valley further reinforced this argument. But Delgado also compared a rhomboidal bone fragment thought to be intentionally pointed, with the rhomboidal bone sagaie points found by Lartet at Aurignac. Although this last parallel is certainly ill founded, Delgado’s suggestions proved to be generally correct. The lower deposit of Casa da Moura does belong to the same (Upper Paleolithic) period as Aurignac and does predate the Epipaleolithic shell middens.

The fact that geological and archaeological reasonings could be combined to produce chronological assessments was clearly dependent on the assumption of the integrity of the in situ lower deposit. Unless the integrity of these red sands could be demonstrated, the statement that the artifacts and the sediments that contained them were contemporary and undisturbed by subsequent events could come under attack on the grounds of Buckland’s theories. Therefore, Delgado had to address the question of how the red sands were laid down. The discussion of this problem, embedded in an exposition of current knowledge on how caves were themselves formed, is a major and most interesting section of the monograph.

He determined that the lower deposit in Casa da Moura had not been washed in by floodwaters because the artifacts, bones, and charcoal it contained were not present in similar “diluvial” deposits found outside the cave, from which the interior deposits were presumably derived. Moreover, such a flooding process