1. - All these four writ petitions involve identical questions of law and fact and, therefore, were heard together and are being decided by this common judgment.

2. The facts of the leading case, namely, S.B. Civil Writ Petition No.2941/1996 - Deep Narain Tiwari v. State of Rajasthan and Others , are being taken as the basis for rendering this decision.

3. Petitioner Deep Narain Tiwari was initially appointed as Ayurved Chikitsak vide order dated 06.09.1984 on adhoc basis. He was granted annual grade increments and also the benefits of revision of pay scales made effective from time to time. The Rajasthan Public Service Commission advertised 1362 posts of Ayurved Chikitsaks in the year 1991, but the process of selection was cancelled, and thus about 1000 Ayurved Chikitsaks, appointed on adhoc/temporary basis from time to time roughly between 1982 and 1993, were ordered to continue as such. An advertisement was issued by the Rajasthan Public Service Commission on 15.03.1995 by which 626 posts of Ayurved Chikitsaks were advertised to be filled in. Most of the Ayurved Chikitsaks, who were appointed and working with the respondent Department on adhoc/temporary basis from 1982 onwards, applied in response to that advertisement. The petitioners, who were selected in pursuance thereof, were offered appointment vide order dated 13.03.1996. An order was issued by the Respondents on 19.03.1996 directing that such adhoc/temporary Ayurved Chikitsaks, who were selected by the Rajasthan Public Service Commission and to whom appointment letters were issued, shall remain posted at the place of their present posting and they may send their joining report accordingly. The petitioners sent their joining report.

4. Thereafter the Government by Notification dated 08.04.1996 added Proviso 5 to Rule 6 and Proviso 6 to Rule 31 of the Rajasthan Ayurvedic, Unani, Homoeopathy and Naturopathy Service Rules, 1973 (for short, 'the Rules of 1973').

5. Proviso 5 to Rule 6 of the Rules of 1973 provides that those appointed as Ayurved Chikitsaks by the Government on adhoc/officiating/urgent temporary basis upto 05.05.1990 and are still continuously working in such capacity on the date this amendment comes into force shall be screened by the committee referred to in Rule 24 for adjudging their suitability for the post of Ayurved Chikitsak.

6. Proviso 6 to Rule 31 provides that the interse seniority of the persons appointed under Proviso 5 to Rule 6 shall be determined by the screening Committee on the basis of length of continuous service and in the cadre they will rank senior to the persons recruited by the Commission in 1995.

7. Aggrieved thereby the petitioners have approached this court challenging the validity of Proviso 6 to Rule 31 added in the Rules of 1973 by the Notification dated 08.04.1996.

8. Shri N.K. Maloo, learned counsel for the petitioners, argued that the petitioners and other persons, selected by the Rajasthan Public Service Commission in an earlier selection, should have been assigned higher seniority than the Ayurved Chikitsaks, appointed on adhoc/officiating/urgent temporary basis upto 05.05.1990, and who were screened and found suitable as a member of service. It was contended that many adhoc/ officiating/temporary Ayurved Chikitsaks, who were screened and regularised in service by taking recourse to Proviso 5 to Rule 6, irrespective of fact whether they faced the selection and not selected or did not face the selection, cannot have a better case than those who successfully faced the selection and secured appointment on the basis of their merit. There are many Ayurved Chikitsaks who were appointed on adhoc/officiating/temporary and later on were selected by the Rajasthan Public Service Commission on the basis of their merit, yet ranked much below. Petitioner Deep Narain Tiwari secured 5th position in the merit-list of selected Ayurved Chikitsaks by the Rajasthan Public Service Commission. The learned counsel for the petitioners argu