25 U.S. Code § 160 - Custody of stocks or bonds held in trust for tribes
All stocks, bonds, or other securities or evidences of indebtedness held by the Secretary of the Interior on June 10, 1876, in trust for the benefit of certain Indian tribes shall, within thirty days from that date, be transferred to the Treasurer of the United States, who shall become the custodian thereof; and it shall be the duty of said Treasurer to collect all interest falling due on said bonds, stocks, and so forth, and deposit the same in the Treasury of the United States, and to issue certificates of deposit therefor, in favor of the Secretary of the Interior, as trustee for various Indian tribes. And the Treasurer of the United States shall also become the custodian of all bonds and stocks which may be purchased for the benefit of any Indian tribe or tribes after the transfer of funds herein authorized, and shall make all purchases and sales of bonds and stocks authorized by treaty stipulations or by acts of Congress when requested so to do by the Secretary of the Interior:
For transfer of functions of other officers, employees, and agencies of Department of the Treasury, with certain exceptions, to Secretary of the Treasury, with power to delegate, see Reorg. Plan No. 26 of 1950, §§ 1, 2, eff. July 31, 1950, 15 F.R. 4935,64 Stat. 1280, set out in the Appendix to Title 5, Government Organization and Employees.