Terra Lycos Chief Executive Bob Davis resigned, less than four months after Madrid-based Terra Networks completed its acquisition of Lycos Inc., the U.S. company Davis led since it was founded in 1995 to compete with Yahoo Inc. and other Internet search services. Terra Lycos also said losses for its fourth quarter widened to $96 million, or 17 cents a share, from a loss of 9 cents a year ago, but better than the 22-cent loss expected by analysts surveyed by First Call/Thomson Financial. Revenue jumped 76% to $164 million. Separately, IDT Corp. filed a lawsuit against Terra Networks and its parent Telefonica for $6 billion, saying it had breached an agreement to form a Spanish-language Internet joint venture in the United States. Shares of Terra Networks fell 75 cents to close at $15.56 on Nasdaq.