Section 16a, act Jan. 12, 1927, ch. 27, 44 Stat. 936, authorized purchases by Department of the Interior without compliance with section 16 of this title.

Section 16b, acts Apr. 17, 1936, ch. 233, 49 Stat. 1226; May 18, 1937, ch. 223, 50 Stat. 181; May 17, 1938, ch. 236, 52 Stat. 393; June 16, 1939, ch. 208, 53 Stat. 834; June 18, 1940, ch. 396, 54 Stat. 474, authorized purchases by Botanic Garden without compliance with section 16 of this title.

Section 16c, act May 13, 1926, ch. 294, 44 Stat. 547, authorized purchases by Architect of Capitol without compliance with section 16 of this title.

Section 16d, act Aug. 4, 1939, ch. 418, § 13, 53 Stat. 1197, authorized purchases by Bureau of Reclamation without compliance with section 16 of this title.