Modern tradition concerning the distinctively Persian custom of celebrating the Nowroose would, if it stood alone, furnish very slight grounds on which to found a far-reaching theory; but historical evidence confirms this tradition to a great extent, by teaching us that the Median and Persian worshippers of Ahura Mazda, and of Mithras, certainly under the Sassinide dynasty, and almost with equal certainty under the Achæmenid kings, kept their calendar and celebrated their religious festivals in a manner differing from that of the surrounding nations; their months were not lunar, their years were not soli-lunar but distinctly solar, and the spring equinox was the date to which as closely as possible the beginning of their year was fixed. In Darmesteter’s translation of the _Zend Avesta_ the Persian months are treated of in Appendix C, p. 33, and in Appendix D, p. 37, we read of the Persian years:-- “L’année était divisée en quatre saisons, correspondant aux nôtres. Cette division ne paraît guère que dans les textes post-avestéens; mais il y a dans l’Avesta même des traces de son existence ancienne. La division normale de l’année est, dans l’Avesta, en deux saisons, été et hiver; l’été, _hama_, qui comprend les sept premiers mois (du 1^{er} Farvardîn au 30 Mihr, soit du 21 mars au 16 octobre).... Cette division a une valeur religieuse, non seulement pour le rituel, mais aussi pour les pratiques, qui varient selon la saison.” The worship of the Persian sun-god Mithras was introduced into Rome about the time of the fall of the Republic. How far this worship differed from that taught in the Zoroastrian writings we need not inquire; however changed it may have been, it was evidently derived originally from a Persian or a Median source. The worship of Mithras, in spite of much opposition, gained many followers in Rome. The birthday of the sun-god was kept at the winter solstice, but the great festivities in his honour, “_the mysteries of Mithras_,” were as a rule celebrated at the season of the spring equinox,[33] and were famous even among Roman festivals. Let us now turn our attention to the Tauric symbolism so closely connected with Mithraic observances in Rome. [33] Cumont, in the first volume of his _Monuments figurés relatifs aux mystères de Mithra_, p. 326, having spoken of the solstitial festival in honour of the birthday of the god, observes as follows: “Nous avons certaines raisons de croire que les équinoxes étaient aussi des jours fériés où l’on inaugurait par quelque salutation le retour des Saisons divinisées. Les initiations avaient lieu de préférence vers le début du printemps, en mars ou en avril....”