(A) Constitution of India , Art.16, Art.162— Seniority of employees - Fixation - Service Rules - Silent as regards fitment of rota and quota and determination of inter-se-seniority - Administrative instructions made by Government would supplement Rules. (Para 6) (B) Constitution of India , Art.16, Art.311— Seniority - Fixation - Rota and quota rule - Vacancy arising for promotees - Promotee fitted into that vacancy - Direct recruits recruited later - Their fitment in order of seniority - Should be determined with reference to rota and quota rule - Promotees thereafter pushed downward in order of seniority - Not illegal. When the Administrative Instructions were followed by Government, in absence of service rule to that effect and rota and quota rule was followed in regard to fixation of seniority between direct recruits and promotees in Central Water Commission Engineering Class-I Service and when a vacancy arose for promotees, a promotee was fitted into that vacancy, the order of Govt. pushing down the promotees thereafter would not be illegal. Consequently, though the direct recruits were recruited later, their fitment in the order of seniority should be determined with reference to rota and quota prescribed under the aforestated administrative i....