During the four decades of Republican rule in the Senate, the position of Senate president was a fairly stable one. Joe Bruno held the job for 14 years. Warren Anderson presided for 15. But since Bruno left the position under a cloud last year, the office has been in flux. Dean Skelos had one of the shorter terms in recent memory, with Democrats taking the majority in last November’s election. And the office may find a new inhabitant, with Malcolm Smith’s hold on the position now tenuous at best. Smith may find company in the annals of Senate history, with the distinct possibility that he could join Joseph Zaretzki, who in 1965 served only one term as Democratic majority leader before Republicans resumed control. Heads are sized according to each Senate president’s length of service.