Thus the great King Vikramaditya vanishes from the historical ground of the sixth century into the realm of myth. With Vikramaditya an often-quoted but ill-authenticated verse occurring in a work of the sixteenth century associates Dhanvantari, Kshapanaka, Amarasimha, Varahamihira, and Vararuchi as among the "nine gems" of his court. With the disappearance of Vikrama from the sixth century A.D. this verse has lost all chronological validity with reference to the date of the authors it enumerates; it is even inadmissible to conclude from such legendary testimony that they were contemporaries. Even though one of them, Varahamihira, actually does belong to the sixth century, each of them can now only be placed in the sixth century separately and by other arguments. Apart from the mythical Vikramaditya, there is now no reason to suppose that court poetry attained a special development in that century, for Harishena's paneygyric, and some other epigraphic poems of the Gupta period, show that it flourished greatly at least two hundred years earlier. None of the other arguments by which it has been attempted to place Kalidasa separately in the sixth century have any cogency. One of the chief of these is derived from the explanation given by the fourteenth-century commentator, Mallinatha, of the word dignaga, "world-elephant," occurring in the 14th stanza of Kalidasa's Meghaduta. He sees in it a punning allusion to Dignaga, a hated rival of the poet. This explanation, to begin with, is extremely dubious in itself. Then it is uncertain whether Mallinatha means the Buddhist teacher Dignaga. Thirdly, little weight can be attached to the Buddhistic tradition that Dignaga was a pupil of Vasubandhu, for this statement is not found till the sixteenth century. Fourthly, the assertion that Vasubandhu belongs to the sixth century depends chiefly on the Vikramaditya theory, and is opposed to Chinese evidence, which indicates that works of Vasubandhu were translated in A.D. 404. Thus every link in the chain of this argument is very weak. The other main argument is that Kalidasa must have lived after Aryabhata (A.D. 499), because he shows a knowledge of the scientific astronomy borrowed from the Greeks. But it has been shown by Dr. Thibaut that an Indian astronomical treatise, undoubtedly written under Greek influence, the Romaka Siddhanta, is older than Aryabhata, and cannot be placed later than A.D. 400. It may be added that a passage of Kalidasa's Raghuvamça (xiv. 40) has been erroneously adduced in support of the astronomical argument, as implying that eclipses of the moon are due to the shadow of the earth: it really refers only to the spots in the moon as caused, in accordance with the doctrine of the Puranas, by a reflection of the earth.