HBO’s Family Tree hasn’t started with very strong viewing roots. The 10:30 PM debut Sunday of the new comedy pulled in 794,000 viewers. That is a big drop off from the 1.2 million who watched its lead-in Veep and down from the 872,000 who tuned in for the debut of Girls in the same slot on April 15, 2012. Over two plays, Family Tree had about 975,000 viewers, down from the 1.1 million Girls had. Bridesmaids’ Chris O’Dowd stars in the mockumentary series co-created by Christopher Guest as a recently single and unemployed thirtysomething who seeks to discover himself by investigating his wacky extended family. The series is set to premiere on BBC2 in the UK this month. Also on HBO, Game Of Thrones’ four-week record viewership streak came to an end Sunday, with the flagship show drawing 4.8 million viewers for its 9 PM broadcast. It’s still a strong number but down from the 5.3 million who watched the 9 PM episode May 5. Over two plays for the night, Thrones had 6 million viewers, down from last week’s 6.8 million. Veep, meanwhile, was even with its Season 2 debut April 14. The Julia Louis-Dreyfus-starring political satire drew 1.5 million viewers over two plays Sunday.