¹³Hutton, Ronald. The Pagan Religions of the Ancient British Isles: Their Nature and Legacy. Oxford, UK: B. Blackwell, 1991. 55-57.
Hutton also describes a ritual practice deduced from evidence found in a Welsh passage tomb: "The most peculiar rite detectable in one of these monuments, however, came not from Ireland but from the Welsh passage grave of Barclodiad y Gawres. The builders had made what virtually all who write upon it cannot help but describe as a 'witches brew': a stew containing oysters, limpets, a winkle, two fish, an eel, a frog, a snake, a mouse and a shrew. This was poured over the cremated bones of two young people laid in the chamber, which had themselves been mixed with the bones of sheep." (54-5)
Wood-Martin considered (and apparently rejected) astronomical associations for the megalithic rock art: "Another idea was, that these figures were designed to represent astronomical phenomena. This notion was perhaps the most obvious, and the least easily disproved. It harmonizes also with what has been handed down respecting the elemental worship of the Pagan Celts. Nevertheless it seems open to obvious objections. In astronomical diagrams, one could hardly fail to recognize a single symbol conspicuous amongst the rest as denoting the sun or moon, or two such symbols denoting both these bodies. One might also expect to see some delineation—even by the rudest hand—of the phases of the moon. We look in vain for these indications of an astronomical reference in the groups of lines and circles. (Wood-Martin, W. G. Pagan Ireland; an Archaeological Sketch: A Handbook of Irish Pre-Christian Antiquities. London: Longmans, Green, and, 1895. 48.)
Archaeologist Robert Hensey suggests that the different theories of the origin and meaning of megalithic art may each contain such truth: "There may be more validity to some previous interpretations than is usually acknowledged, but because we are constantly in the process of shelving the last account in favour of a newer or more theoretically sophisticated one we generally fail to allow for this. Often the issue is not whether a particular interpretation has validity or not but rather that archaeologists have tried to put their interpretation of the art forward as exclusively correct. Yet, when the time-depth and stylistic variety of the art is taken into account we realise that there may be more than one passage tomb art and hence more than one valid explanation." (Hensey, Robert. "Assuming the Jigsaw Had Only One Piece: Abstraction, Figuration and the Interpretation of Irish Passage Tomb Art." Visualising the Neolithic: Abstraction, Figuration, Performance, Representation. Ed. Andrew Cochrane and Andrew Jones. Oakville, CT: Oxbow, 2012. 161.) In this article Hensey also quotes Professor Muiris O Suilleabhain in a comment about the study of megalithic art during the 1990s: "Research into the meaning of the art was regarded as something of a cul-de-sac by many archaeologists and the field was effectively abandoned to pseudo-scientists." (O'Sullivan, M. 1996. comment on "Entering alternative realities: cognition, art and architecture in Irish Passage Tombs" by J. Dronfield. Cambridge Archaeological Journal 6.1, (1996): 59.)
A journal in 1996 humorously suggested that "[prehistoric art's] function is analogous to graffiti - that it could have been produced mostly by young Homo sapiens males who were luring young females down into this cave and saying: 'Here, look at those bison I've drawn, aren't they cool?'" ("Spoil Heap." Archaeology Ireland 10.1 (1996): 36.)