There is reason to believe that Artaxerxes, some short time before his death, invested Sapor with the emblems of sovereignty, and either associated him in the empire, or wholly ceded to him his own place.  The Arabian writer, Macoudi, declares that, sated with glory and with power, he withdrew altogether from the government, and, making over the administration of affairs to his favorite son, devoted himself to religious contemplation.  Tabari knows nothing of the religious motive, but relates that towards the close of his life Artaxerxes “made Sapor regent, appointed him formally to be his successor, and with his own hands placed the .crown on his head.” [PLATE XII.] These notices would, by themselves, have been of small importance; but force is lent to them by the facts that Artaxerxes is found to have placed the effigy of Sapor on his later coins, and that in one of his bas-reliefs he seems to be represented as investing Sapor with the diadem.  This tablet, which is at Takht-i-Bostan, has been variously explained, and, as it is unaccompanied by any inscription, no certain account can be given of it; but, on the whole the opinion of those most competent to judge seems to be that the intention of the artist was to represent Artaxerxes (who wears the cap and inflated ball) as handing the diadem to Sapor—­distinguished by the mural crown of his own tablets and coins—­while Ormazd, marked by his customary baton, and further indicated by a halo of glory around his head, looks on, sanctioning and approving the transaction.  A prostrate figure under the feet of the two Sassanian kings represents either Artabanus or the extinct Parthian monarchy, probably the former; while the sunflower upon which Ormazd stands, together with the rays that stream from his head, denote an intention to present him under a Mithraitic aspect, suggestive to the beholder of a real latent identity between the two great objects of Persian worship.

[Illustration:  PLATE 12.]

The coins of Artaxerxes present five different types. [PLATE XI., Fig. 1.] In the earliest his effigy appears on the obverse, front-faced, with the simple legend AETaHsnaTE (Artaxerxes), or sometimes with the longer one, BaGi ARTaiiSHaTR MaLKA, “Divine Artaxerxes, King;” while the reverse bears the profile of his father, Papak, looking to the left, with the legend BaGi PAPaKi MaLKA, “Divine Papak, King;” or BaBl BaGi PAPaKi MaLKA, “Son of Divine Papak, King.”  Both heads wear the ordinary Parthian diadem and tiara; and the head of Artaxerxes much resembles that of Volagases V., one of the later Parthian kings.  The coins of the next period have a head on one side only.  This is in profile, looking to the right, and bears a highly ornamental tiara, exactly like that of Mithridates I. of Parthia, the great conqueror.  It is usually accompanied by the legend MaZDiSN BaGi ARTaHSHaTR MaLKA (or MaLKAN MaLKA) aiean, i.e.  “The Ormazd-worshipping Divine Artaxerxes, King of Iran,” or “King of the Kings of Iran.”