The present-day language of Ariana is the latest evolutionary form of "Dari" and is known as "Farsi" or the Dari language. The people of Ariana them­selves, however, have always employed the word "Dari" for whatever lan­guages have flourished in the country. In the past the two languages under discussion which flourished simultaneously have been known as the "Dari Dari" and the "Pahlawi Dari."

The Dari language of today, namely, Dari, originated, as mentioned above, during the Muslim period in the east of Ariana. The important centres of this language were the cities of Transoxiana and Khurasan, to wit, Samar­qand, Bukhara, Balkh, Merv, Herat, Tiis, and Nishapiir. These centres

extended even to Sistan. This explains why the most eminent poets of this language down to the Salj 5q period hailed from these particular cities. Gradually, Dari expanded from Khurasan and Transoxiana to other parts of Ariana, so that by the Ghaznawid period it had extended to Gurgan, Damg_han, and Rayy, and by the Saljdq era it had travelled as far away as AharbAijan, Isbahan, and Hamadan. In the province of Fars it did not achieve the status of a popular language even in the days of Sa'di and Ilafiz. That is why these two great poets have revelled in the mastery of this language and in the expres­sion of their poetic genius through it. Both of them also composed verse in the Pahlawi dialect of Fars, popularly known as the Shirazi language.

The rules of prosody of Arabic poetry were formulated by Khalil ibn Abmad. These were assiduously observed by the Aryan writers in their Dari works. Considerable literature was produced on the subject both in Ariana and in the Indo-Pakistan sub-continent. Consequently, the same Arabic names were retained for Dari metres and rhymes, so much so that even the same Arabic word a/d`il was employed for purposes of scansion. Metres can be classified into three groups, i.e., metres common to both Arabic and Dari, metres which were the outcome of the Aryan genius and did not exist earlier, and metres which were, on the reverse, typical of and exclusive to Arabic poetry.

Amongst the exclusively Dari metres the most well-known is the one employed in the quatrains of Baba Tahir `Uryan of Hamadan. In the pre­Islamic times right up to the Achaemenian period the only verse known was the blank verse. Specimens of poetry preserved in the Avesta and Old Dari are all composed in blank verse. This type of poetry was also in vogue in Pahlawi and Dari, the two languages so closely related to each other.

The forms of Dari verse have also an independent character and they have not always followed the Arabic pattern. The "mathnawi," "tarjs'-band," "tarkib-band," "musammat," "muthallath,"` "murabba`," "mukhammas," "mustazad," and "rubd`i" are all exclusive to Dari poetry, and they have originated solely in the Dari genius. Dari verse has also influenced Urdu and Turkish poetry. Similarly, the rhymed verse and many figures of speech owe their origin to the creative genius of the Aryan mind. "Muwashs_hah" and "mulamma"' are also Dari in origin.