The thirteen Trivandrum plays show some irregularities in their verse parts, although not many. In two plays no irregularity occurs at all: the Ûrubhanga and the Karnabhâra (Sukthankar 1921:129). The grammatical irregularities in the remaining plays are of several types, namely the use of the âtmanepada instead of the parasmaipada, the use of the parasmaipada instead of the âtmanepada, change of conjugation, irregular compounds, irregular samdhi, confusion of gender, and a limited number of other irregularities.
A warning should be made on this point. As the conclusions below are reached often on the basis of a sole occurrence, the truth can be very different. It is difficult to conclude anything safely from such an enumeration for two reasons. Firstly, some irregularities may be considered serious errors while others are only accepted alternatives. Secondly, as to the presence of errors, it still remains a problem as to the responsible person, the author or a copyist. And thirdly, it is possible that a number of irregularities in the manuscripts have not been adopted in the editions. Nevertheless, there are several observations possible, if we consider only the most irregular formations or uses.
First of all, the grammatical irregularities confirm the existence of one pair, namely Karnabhâra and the Ûrubhanga. These two plays are characterized by the absence of grammatical irregularities. Secondly, on the ground of samâshvas- it is likely that the Pratimâ on the one hand, and Abhisheka on the other hand do not have a common author, as the former applies correct simplex forms, while the latter confuses the simplex with the causative. And thirdly, as the Avimâraka, which belongs to the same group as the Pratimâ, employs correct forms too, it must indeed be very close to the Pratimâ.