Matsya Purana 273.68

273.68

ailañcekṣvākuvaṃśañca prakṛtiṃ paricakṣate.
rājānaḥ śreṇibaddhāśca tathānte kṣatriyā bhuvi .. 273.67

Hear, I will relate to you the double origin of the modern Kṣatriya Kings. Aila and Ikṣwâku dynasties are said to be the origin of the Kshatriyas.—67-68

The Kings and other common Kṣatriyas were variously sub-divided in the world. Quite a profusion of Kṣatriyas were born in the Aila dynasty, but there were not so many in the Ikṣwâku dynasty. Their number is full one hundred. Similarly, by the spread of the Bhoj dynasty that number was doubled.—69-70