YORKSHIRE took three wickets during the opening afternoon at Scarborough as Somerset reached tea 200-7 from 64 overs.
The visitors advanced from 71-4 at lunch, with Adam Hose's 62 marking his second fifty in three career County Championship matches.
Liam Plunkett trapped Steve Davies lbw for 16 before Ben Coad bowled Jim Allenby through the gate for 19.
Hose reached 50 off 98 balls, his second in two matches against Yorkshire having hit 68 in defeat at Taunton last month.
He then fell in the closing stages of the session when he was bowled by an Adil Rashid googly, leaving the score at 180-7 in the 60th over.
Craig Overton hit Rashid for six over long-on in the final over of the session to bring up the 200, with captain Lewis Gregory taking tea on 21 not out.
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