44 Asimis in Tegulis.
agricultural deity ; Dius Fidius is perhaps an offshoot of luppiter, while Hercules is simply the Greek Herakles, naturalised in Rome very early as a god of merchants, and identified by some with Dius Fidius ; hence probably the tabu. What have they in common that they should be treated alike in this respect ? This at least, that they are all well-disposed, and consequently should not be brought under the influence of roof-magic, which we have seen is mostly bad. The only other explanation I know of, that of Usener,^ who calls attention to the common practice of swearing in the open air, in order to have, literally, God before one's eyes, is hardly applicable here, for the deities in question are not sky-gods, except perhaps Dius Fidius, and he in one aspect (Semo Sancus) is agricultural also. One may compare the fetish of Terminus on the Capitol and the famous marks of Poseidon's trident on the Akropolis at Athens, neither of which may be roofed over.
But I do not consider here the classical objection to being under the same roof with a murderer or other notoriously impious person, which finds its most familiar expression in Horace [Od. HI. ii. 26 If.), and in the legend of Orestes. The roof here is, I think, merely incidental ; to be under the same roof with anyone, in the small houses of antiquity, is to be near him, and that is what is objected to. As Horace re- reminds us, it is equally dangerous to be on the same ship.
HI. The Roof and Birth. In the first of the great crises of life, it may be said, broadly, that the roof plays no part unless something goes wrong or is likely to go wTong. The navel-cord of a Hopi child is sometimes put in it,^ and in Patalima, in cases of difficult labour, a little oftering of tobacco is stuck into the thatch and the ancestral spirits called upon to come and help. But far more usually, the efforts of the expectant mother's friends are directed towards driving someone away from the roof. The Jewish
1 Gdtternamen, chap, on " Die Verehrung des Lichtes."
2 Man, 1921, 58 (p. 100).
