Unless a contrary intent is clearly expressed in the instrument, the authority to invest in specified types of investments includes authorization to invest in a mutual fund, or in any common or collective trust fund established and maintained by a corporate fiduciary, or by any affiliate of a corporate fiduciary within the meaning of section 1504 of the Internal Revenue Code of 1986 (Public Law 99-514, 26 U.S.C. § 1504) or any successor provision, if the portfolio of the mutual fund or of the common or collective trust fund consists of the specified types of investments and is otherwise in conformity with the laws of this Commonwealth and of the United States.