Petitioner is the holder of a bond of respondent Reclamation District No. 784, which was one of an issue of 1921 secured by assessments levied upon lands in the district. A call for payment of assessments to meet bonds was made in 1937. In response thereto Farm Land Investment Company, an owner of land in the district against which assessments were a lien, paid them with matured bonds of the district and the lien was cancelled by respondent Bossen, County Treasurer, bond fund custodian of the district. Respondent Bosse acquired the land involved from the company. Petitioner prays for a writ of mandate compelling the sale of the above-mentioned land upon the theory that the assessments are delinquent because there was no lawful authority to accept the bonds in payment of them. Intervener holds bonds of the same issue.

At the time of the issuance of the bonds, section 3480 of the Political Code, the statute under which the bonds were issued, contemplated payment of assessments in cash. However, purchasers at a sale after delinquency or by the treasurer, after deed to him, were authorized to pay the purchase price in bonds. (Stats. 1917, p. 1181.) In 1923 a paragraph was added to section 3480 reading:

“Any land owner of the district who shall desire at any time to lessen or remove the lien upon his land of any assessment on which bonds have been or hereafter may be issued may deliver to the county treasurer for cancellation any bonds payable out of said assessment, and the treasurer shall credit against the assessment on his land the principal and accrued interest of said bonds.” (Stats. 1923, p. 598.) It was pursuant to that paragraph that Farm Land Investment Company paid the 1937 assessment call with bonds.

It has been held that to apply that paragraph to bonds issued before its enactment would be a violation of the impairment of contracts clause of the Constitution (Hershey v. Cole, 130 Cal.App. 683 [ 20 P.2d 972 ]; see 85 A.L.R. 242 ; 97 id. 911) on the principle that the terms of the statute under which the bonds are issued become a part of the contract with the bondholder which cannot be impaired by subsequent amendment. (See 85 A.L.R. 242 ; 97 id. 911.) Assuming the soundness of that proposition, and its applicability here, inasmuch as the bonds were issued prior to 1923, when the paragraph was added to section 3480, we come to the statute adopted in 1941, reading:

“No action or proceeding to contest the validity of any credit on or payment of all or any portion of an assessment levied by a reclamation district which has heretofore been made pursuant to the provisions contained in Section 3480 of this code at the date of such credit or payment, may be commenced unless commenced within six months from the effective date of this section or the date of such credit or payment, whichever is the later date.” (Pol. Code, § 3480g, added by Stats. 1941, ch. 145.) It is urged that to hold that the instant proceeding is barred thereunder would be an impairment of the bondholder’s contract; that the period of time is unreasonably and arbitrarily short; and that an unreasonable burden is placed on the bondholders if they must keep, at their peril, constant watch upon the proceedings for collection of assessments although there is no default in the principal or interest on their bonds.

We find no impairment of the bondholder’s contract by section 3480g. Assuming his contract embraces the right to have the assessments paid in cash and that all remedies for the enforcement of that contract cannot be taken away, section 3480g does not purport to achieve that result. It merely fixes a time limit during which he may assert the right. True, it may be that he must be more vigilant in keeping a watch on whether the district officials are performing the terms of the contract such as levying the assessments to pay the bonds and collecting them in the proper medium, but it is his contract and he has an obligation to ascertain whether or not it is being performed. It has heretofore been held that an action on the bond must be commenced within four years from its maturity date. (Irvine v. Bossen, 25 Cal.2d 652 [ 155 P.2d 9 ].) Holders of nonmatured bonds upon which the interest has been paid may not have the same reason to suspect that collections are not being made in cash that would tend to motivate holders of matured bonds or those with interest in default. But they presumably are familiar with the statute—the terms of their contract and must be guardians of their own interests. In Coombes v. Getz, 217 Cal. 320 [ 18 P.2d 939 ], this court was considering the statute of limitation on a constitutionally given right of action against the officers of a corporation for embezzlement. It was contended that the statute of limitation was invalid because it impaired the constitutional right when it was applied where plaintiff did not know of the embezzlement. To this the court replied that:

‘ ‘ This restriction upon legislative action does not, however, extend to reasonable statutory limitations within which this constitutional right may be enforced.” Likewise, in the instant case the Legislature is authorized to place reasonable limitations upon a constitutionally protected right. It is not new that a mandamus proceeding may be barred by a statute of limitation where action is sought to compel officials to perform duties in connection with the collection of taxes or assessments to pay bonds. (See Barnes v. Glide, 117 Cal. 1 [ 48 P. 804 , 59 Am.St.Rep. 153 ].) We cannot agree that under section 3480g a bondholder’s action might be barred before it accrues. That assumes that he could not bring an action to compel the collection of assessments in cash rather than bonds before there was a default in payment of his bonds. It would probably rarely happen that the acceptance of bonds instead of cash would not be immediately followed by a default in either principal or interest. But in any event the section may be interpreted to fix by implication the time when an action accrues to contest the validity of a credit on or payment of an assessment as well as the time within which the action must be commenced. So viewed the issue is solely one of the reasonableness of the time limit.

The general rule with regard to retroactive operation of statutes of limitation is stated in Rosefield Packing Co. v. Superior Court, 4 Cal.2d 120, 122 [ 47 P.2d 716 ]:

“This argument, though often made heretofore, has been answered and almost uniformly overruled by the highest authorities. It is well settled that a reasonable limitation of the time within which a matured contractual obligation may be enforced by suit does not impair the obligation of the contract in the sense of the constitutional prohibition cited; and it has been often held that a limitation to one year, and even to six months, is not unreasonable, and does not impair the obligation of the contract nor deprive the obligee of an adequate remedy.” What constitutes a reasonable time is primarily a question for the Legislature and a court will not overrule its decision except where palpable error has been committed. (Terry v. Anderson, 95 U.S. 628 [ 24 L.Ed. 365 ]; Wilson v. Iseminger, 185 U.S. 55 [ 22 S.Ct. 573 , 46 L.Ed. 804 ]; Mills v. Scott, 99 U.S. 25 [ 25 L.Ed. 294 ].) Tested by that rule we cannot say the period of six months here specified is unreasonable. Consideration must be given to the circumstances that the collection of the assessments as required by the statute is a part of the bondholder’s contract of which he is presumed to be aware. He also should know that the establishment of statutes of limitation are always a legislative prerogative. The mode of payment or crediting assessments is merely one of the things required to be done under his contract. There is always the power to levy supplemental assessments. (Irvine v. Reclamation Dist. No. 108, 24 Cal.2d 468 [ 150 P.2d 428 ].) Any delay in questioning the validity of an assessment payment or credit tends to disturb the orderly procedure of assessment collection, the performance of the duties by the officials, the orderly payment of bonds and the stability of the titles of landowners. The statute authorizing the payment of assessments with bonds was adopted in 1923 but it was not until in 1933 that Hershey v. Cole, supra, laid down the rule that it did not apply to bonds issued prior to that time. There probably have been many instances throughout the state in which the' custodian of bond funds has accepted bonds in payment of assessments although the bonds were issued prior to the 1923 amendment. These factors not only justified the length of the period of time fixed by the Legislature but also the adoption of a limitation period. True the statute is part of the bondholder’s contract but not every alteration in his remedies or rights is an unconstitutional impairment of his contract. Thus, in Keefe v. Clark, 322 U.S. 393 [ 64 S.Ct. 1072 , 88 L.Ed. 1346 ], the statute under which bonds secured by assessments were issued provided for supplemental assessments if the original assessment proved inadequate to pay the bonds. A subsequent statute declared all land which was sold for taxes would be relieved from all assessment charges, thus making it not subject to a supplemental assessment. The court held the statute valid, stressing the fact that the contract obligation to levy a supplemental assessment was not on the face of the bond itself. Likewise, in the instant case there is nothing on the face of the bonds requiring that assessments must be paid in cash, specifying the remedy of a bondholder or the time within which he may pursue it. The court went on to state at page 397:

Reliance is placed upon the series of cases including McGahey v. Virginia, 135 U.S. 662 [ 10 S.Ct. 972 , 34 L.Ed. 304 ], and In re Brown, 135 U.S. 662, 701 [ 10 S.Ct. 972 , 34 L.Ed. 304 ]. In those cases the State of Virginia had issued interest coupons which were made receivable in the payment of taxes and other debts due the state. By various methods the state Legislature sought to impair that right. In the Brown case the statute placed a limit of a year in which to test the validity of a coupon. Otherwise, it could not be used in the payment of taxes. The court held the period unreasonable but conceded that each case must rest upon its own circumstances. It pointed out factors that do not exist in the instant case.- It said at page 707:

Intervener advances other arguments why the petition should not be granted, such as that petitioner’s bonds are barred by the statute of limitation under the rule announced in Irvine v. Bossen, supra, and pendency of another action, but inasmuch as we have determined that this proceeding is barred by section 3480g of the Political Code it is unnecessary to discuss them.

The alternative writ is discharged and the petition for a peremptory writ is denied.

Gibson, C. J., Shenk, J., Edmonds, J., Traynor, J., and Sehauer, J., concurred.