Iowa Const. art. VIII, § 7
If a state bank be established, it shall be founded on an actual specie basis, and the branches shall be mutually responsible for each other’s liabilities upon all notes, bills, and other issues intended for circulation as money.*
*Codified Iowa Constitution, Art. VIII, §6 – 11 apply to banks of issue only, see 63 Iowa 11, 220 Iowa 794, and 221 Iowa 102