And on Friday, St. Laurent Paperboard of Canada said it was in merger talks. It did not specify with whom, but the name swirling around Wall Street was that of Smurfit-Stone Container, the world's biggest corrugated-box maker -- itself formed when Jefferson Smurfit gobbled up the Stone Container Corporation in 1998. Despite all the mergers, paper remains a highly fragmented industry. ''You can still find 30 or 40 publicly traded paper companies in the U.S., and probably another 15 in Canada,'' said Mark Wilde of Deutsche Banc Alex. Brown, noting that even International Paper, the industry leader, accounts for only about 5 percent of the 300 million tons of paper produced worldwide each year. The lack of cohesion has cost the industry dearly. Most companies expanded wildly when paper prices started to soar in the mid-90's. When economic troubles overseas put the brakes on demand, the industry found itself drowning in capacity.