Acquisition activity lifted the market higher Monday led by Yule Catto & Co, John Wood Group and Wellstream Holdings.Shares in chemicals group Yule Catto leapt ahead as it unveiled the acquisition of German group PolymerLatex for €157m (£133m) and promised big efficiency benefits from the deal.A 4 for 3 rights issue at 116p to raise £225m will fund the purchase."PolymerLatex Group, headquartered in Germany, is a compelling, transformational opportunity for Yule Catto to acquire a leading emulsion polymers franchise," the group said. Oilfield services mid-cap John Wood Group is buying rival PSN for $955m (£607m). PSN will be merged with Wood's production facilities business, creating Wood Group PSN. It will be run by PSN's chief executive Bob Keiller who'll also join the board.In a separate statement, Wood reported continued progress at most of its key divisions and thinks the overall performance for 2010 is likely to be slightly ahead of expectations. Also in the oil equipment and services sector, America's General Electric is paying almost £800m for Britain's Wellstream. An initial approach in September valued at 750p a share was firmly rejected, but 780p plus a 6p special dividend proved too tempting. FTSE 250 - RisersYule Catto & Co (YULC) 290.00p +11.54%John Wood Group (WG.) 521.00p +6.72%Wellstream Holdings (WSM) 790.00p +5.76%Savills (SVS) 387.70p +5.64%Fenner (FENR) 337.60p +5.01%Kenmare Resources (KMR) 27.47p +4.85%Dairy Crest Group (DCG) 396.30p +4.56%Spectris (SXS) 1,267.00p +4.37%CPP Group (CPP) 285.00p +3.75%Henderson Group (HGG) 131.90p +3.69%FTSE 250 - FallersRedrow (RDW) 128.10p -5.46%JD Wetherspoon (JDW) 435.00p -4.40%Taylor Wimpey (TW.) 28.34p -2.98%Berkeley Group Holdings (BKG) 885.00p -2.85%Bovis Homes Group (BVS) 387.00p -2.71%Persimmon (PSN) 406.90p -2.61%Drax Group (DRX) 376.00p -2.54%Barratt Developments (BDEV) 87.35p -2.46%Bellway (BWY) 636.50p -2.08%Regus (RGU) 80.00p -1.96%