opinion: PER CURIAM.
  Appellants Norman Dodd and Aaron M. Sargent, two of three trustees named in a joint venture agreement with Ap-pellee Pioche Mines Consolidated, Inc., have appealed to this Court from an Order of the trial court denying their motion to be substituted as counter-claimants in this litigation.
  In reaching our decision here we are assuming, without deciding, that the order denying the motion for substitution is appealable.
  The substitution or joinder of Appellants as counterclaimants rested in the discretion of the district court and was not mandatory. Rule 25(c), Federal Rules of Civil Procedure, 28 U.S.C.A.; Virginia Land Co. v. Miami Shipbuilding Corp., 201 F.2d 506 (5th Cir.1953); Sun-Maid Raisin Growers of California v. California Packing Corporation, 273 F.2d 282 (9th Cir.1959).
  On an examination of the record we are satisfied that the district court did not abuse its discretion in denying the motion of Appellants.
  Affirmed.