At the end of the first book of Cicero's De diuinatione there occurs a tantalising passage containing a specific mention of the ‘Isiac diviners.’ It used to be attributed to Ennius by the earlier editors of that author, but since the time of Bothe this view has not been generally accepted. The passage runs ‘non habeo denique nauci Marsum augurem, non vicanos haruspices, non de circo astrologos, non Isiacos coniectores, non interpretes somniorum; non enim sunt ii aut scientia aut arte divini.’ The text is sound and there is no variant reading for the words ‘Isiaci coniectores’ which interest us most particularly in this study. The Italian colour of the passage (cf. ‘Marsus augur, de circo astrologi’) excludes the possibility of a Greek origin, and the question is merely to whom, Ennius or Cicero, the words ‘Isiaci coniectores’ should be assigned. It must be admitted that the words ‘non habeo … divini’ are not metrical and it would be hopeless to defend them in their present form as the ipsissima verba of Ennius. But the possibility that they contain a more or less close paraphrase of Ennius is suggested by the use of ‘non habeo … nauci,’ a phrase which Cicero never used. ‘Isiacus’ too is a rare word, which does not appear elsewhere in Republican Latin (v. infra pp. 58, 59, n. 21 and 22).