The Rajput killed his daughter because it was a disgrace to him to get her married at all outside his clan, and she could not be married within it.

Afterwards the disgrace was removed by marrying her into a higher clan than his own and by lavish expenditure on the wedding; and the practice of female infanticide was continued to avoid the ruinous outlay which this primitive view of marriage had originally entailed.

The Hindu custom of the Swayamvara or armed contest for the hand of a Rajput princess, and the curious recognition by the Hindu law-books of simple rape as a legitimate form of marriage would be explained on the same ground.
73.

The exogamous clan with male descent and the village.
It has been seen that the exogamous clan with female descent contained no married couples, and therefore it was necessary either that outside men should live with it, or that the clans should continually meet each other, or that two or more should live in the same village.

With the change to male descent and the transfer of women to their husbands' clans, this unstable characteristic was removed.