Mr. Justice Blackmun
delivered the opinion of the Court.
On the merits, this case raises the same question as to the constitutionality of §§ 202 (d)(3) and 216 (h)(3) (C)(ii) of the Social Security Act, 64 Stat. 484, as amended, and 79 Stat. 410, 42 U. S. C. §§ 402 (d) (3) and 416 (h) (3) (C) (ii), as was presented in Mathews v. Lucas, ante, p. 495. The present litigation, however, also raises certain jurisdictional issues. It now has become apparent that the simultaneous submission of Lucas to the Court, and our decision in that case today, make it unnecessary for us specifically to decide the jurisdictional questions.
I
Appellant Gregory Norton, Jr., was born out of wedlock in February 1964. Both his father and his mother then were high school students, aged, respectively, 16 and 14, who lived separately at home with their parents. The two never married and, indeed, never lived together. Appellant always has resided with his maternal grandmother and has been cared for by her. When Gregory was born, his father contributed six dollars and some clothing and other habiliments for the baby, but, being so young and unemployed, he never assumed appellant’s actual support.
In February 1965 the father entered military service. He was killed in Vietnam on May 19, 1966, at age 19. Before his death, the father apparently took some initial steps (the procurement of a birth certificate and other items) necessary for the processing of a dependent child’s military allotment. The father failed, however, to complete the required procedures before he was killed.
In September 1969 appellant’s maternal grandmother filed on his behalf an application for a surviving child’s benefits under § 202 (d)(1) of the Act, 42 U. S. C. § 402 (d)(1), based on the father’s earnings record. An administrative hearing followed. The Hearing Examiner concluded that appellant was not entitled to benefits as a dependent child because his father, at the time of his death, was neither living with appellant nor contributing to appellant’s support. App. 13-19. The subsequent administrative appeal was no more successful. Id., at 20-21.
The present action was then instituted on behalf of appellant against the Secretary of Health, Education, and Welfare. By the complaint, relief was sought alternatively on statutory and constitutional grounds. First, it was asserted that, by his attempt to secure a military allotment for appellant, the father, at the time of his death, in fact was contributing to appellant's support, within the meaning of § 216 (h) (3) (C) (ii) of the Act, and that appellant therefore was a dependent of the father, under §§ 202 (d)(1) and (3) (1970 ed. and Supp. IV), and entitled to benefits. Second, it was asserted that, by creating a presumption of dependency, and consequent qualification for benefits, for legitimate children generally, and for illegitimate children under certain, circumstances, see n. 1, but denying the presumption to appellant and others similarly situated, the Act discriminated against appellant's class, in violation of the guarantee of equal protection implicit in the Due Process Clause of the Fifth Amendment.
Appellant’s statutory claim was initially considered and rejected by a single District Judge. Norton v. Richardson, 352 F. Supp. 596 (Md. 1972). In view of the complaint's request for certification of a class pursuant to Fed. Rule Civ. Proc. 23 (c)(1), and for classwide injunc-tive relief against the alleged unconstitutional operation of the Act's presumptions of dependency, a three-judge court was convened under 28 U. S. C. §§ 2282 and 2284 (1970 ed. and Supp. IV) to pass upon the constitutional claim. The three-judge court first agreed with, and reaffirmed, the single judge’s rejection of appellant’s statutory claim. Norton v. Weinberger, 364 F. Supp. 1117, 1120 (1973). The court went on to identify the plaintiff class, id., at 1120-1121, but on the merits of the constitutional claim it ruled in favor of the Secretary and granted summary judgment in his favor. Id., at 1121— 1131.
Appellant, taking the position that the three-judge court had denied his request for an order enjoining enforcement of provisions of the Act, lodged a direct appeal here pursuant to 28 U. S. C. § 1253. While his jurisdictional statement was pending, Jimenez v. Weinberger, 417 U. S. 628 (1974), was decided. This Court thereafter vacated the three-judge court’s judgment and remanded the case for further consideration in the light of Jimenez. Norton v. Weinberger, 418 U. S. 902 (1974).
On the remand, the same three-judge court, with one judge now dissenting, adhered to its earlier conclusion in favor of constitutionality. Norton v. Weinberger, 390 F. Supp. 1084 (1975). Appellant has again appealed. We postponed the question of jurisdiction to the hearing of the case on the merits, 422 U. S. 1054 (1975), and, in doing so, cited Weinberger v. Salfi, 422 U. S. 749, 763 n. 8 (1975), which just then had been decided. Subsequently, we set the case for oral argument with Mathews v. Lucas, ante, p. 495. 423 U. S. 819 (1975).
II
The question whether the three-judge court was properly convened upon appellant’s demand for injunctive relief is relevant, of course, to our appellate jurisdiction. If the court was not empowered to enjoin the operation of a federal statute, then three judges were not required to hear the case under 28 U. S. C. § 2282, and this Court has no jurisdiction under 28 U. S. C. § 1253. Accordingly, appellant and the Secretary have debated whether the District Court possessed injunctive power under § 205 (g) of the Act, 42 U. S. C. §405 (g), and whether, in the light of § 205 (h), 42 U. S. C. § 405 (h), relief was available under the mandamus statute, 28 U. S. C. § 1361, or under the Administrative Procedure Act, 5 II. S. C. § 701 et seg.
We think it unnecessary, however, to resolve the details of these difficult and perhaps close jurisdictional arguments. The substantive questions raised on this appeal now have been determined in Mathews v. Lucas, ante, p. 495. This disposition renders the merits in the present case a decided issue and thus one no longer substantial in the jurisdictional sense.
Assuming that the three-judge court was correctly convened, and that we have jurisdiction over the appeal, the appropriate disposition, in the light of Mathews v. Lucas, plainly would be to affirm the judgment entered in this case in favor of the Secretary. Assuming, on the other hand, that we lack jurisdiction because the three-judge court was needlessly convened, the appropriate disposition would be to dismiss the appeal. When an appeal to this Court is sought from an erroneously convened three-judge district court, we retain the power “ ‘to make such corrective order as may be appropriate to the enforcement of the limitations’ ” which 28 U. S. C. § 1253 imposes. Bailey v. Patterson, 369 U. S. 31, 34 (1962), quoting Gully v. Interstate Natural Gas Co., 292 U. S. 16, 18 (1934). What we have done recently, and in most such cases where the jurisdictional issue was previously unsettled — and we do not imply that our doing so is statutorily or otherwise compelled — has been to vacate the district court judgment and remand the case for the entry of a fresh decree from which an appeal may be taken to the appropriate court of appeals. Gonzalez v. Employees Credit Union, 419 U. S. 90, 101 (1974), is an example. In the present case, however, the decision in Lucas has rendered the constitutional issues insubstantial and so much so as not even to support the jurisdiction of a three-judge district court to consider their merits on remand. See, e. g., Hicks v. Miranda, 422 U. S. 332, 343-345 (1975); Hagans v. Lavine, 415 U. S. 528, 536-538 (1974). Thus, there is no point in remanding to enable the merits to be considered by a court of appeals. See McLucas v. DeChamplain, 421 U. S. 21 (1975).
It thus is evident that, whichever disposition we undertake, the effect is the same. It follows that there is no need to decide the theoretical question of jurisdiction in this case. In the past, we similarly have reserved difficult questions of our jurisdiction when the case alternatively could be resolved on the merits in favor of the same party. See Secretary of the Navy v. Avrech, 418 U. S. 676 (1974). The Court has done this even when the original reason for granting certiorari was to resolve the jurisdictional issue. See United States v. Augenblick, 393 U. S. 348, 349-352 (1969). Although such a disposition would not be desirable under all circumstances, we perceive no reason why we may not so proceed in this case where the merits have been rendered plainly insubstantial. Cf. McLucas v. DeChamplain, 421 U. S., at 32. Making the assumption, then, without deciding, that our jurisdiction in this cause is established, we affirm the judgment in favor of the Secretary on the basis of our decision in Mathews v. Lucas, ante, p. 495.
It is so ordered.
Section 202 (d) (1) provides survivorship benefits only to a child who was “dependent” upon the deceased insured parent at the time of the parent’s death. A legitimate child, a child entitled under the intestacy laws of the insured parent’s domicile to inherit personal property from the parent, a child whose illegitimacy results from a formal defect in the parents’ purported marriage ceremony, and a child acknowledged in writing by the insured father as his son or daughter or judicially decreed (during the father’s lifetime) to be such, are all deemed under the Act to be dependent upon the parent, unless the child has been adopted by some other individual, and thus are relieved of otherwise proving actual dependency. §§202 (d)(1), 202 (d)(3), 216(e), 216(h)(2), and 216(h)(3) (C)(i), 42 U. S. C. §§402 (d)(1), 402 (d)(3), 416 (e), 416 (h)(2), and 416 (h) (3) (C) (i) (1970 ed. and Supp. IV). Since appellant did not come within any of these categories, he could establish his status as a dependent child under the Act only by showing that his father lived with him or contributed to his support at the time of his death. §§202 (d)(3) and 216 (h) (3) (C) (ii), 42 TJ. S. C. §§402 (d)(3) and 416 (h) (3) (C) (ii). See generally Mathews v. Lucas, ante, p. 495.
The definition of the class, however, does not appear to have been formalized in the three-judge court’s judgment. App. 59.
In contrast to the situation in Weinberger v. Salfi, 422 U. S. 749, 763 n. 8 (1975), there is no jurisdiction here under 28 U. S. C. § 1252, since the District Court’s decision was in favor of the statute’s constitutionality.
Section 205 (g) reads in pertinent part:
“Any individual, after any final decision of the Secretary made after a hearing to which he was a party, irrespective of the amount in controversy, may obtain a review of such decision by a civil action .... Such action shall be brought in the district court of the United States for the judicial district in which the plaintiff resides .... As part of his answer the Secretary shall file a certified copy of the transcript of the record including the evidence upon which the findings and decision complained of are based. The court shall have power to enter, upon the pleadings and transcript of the record, a judgment affirming, modifying, or reversing the decision of the Secretary, with or without remanding the cause for a rehearing.”
Section 205 (h) reads in pertinent part:
“The findings and decisions of the Secretary after a hearing shall be binding upon all individuals who were parties to such hearing. No findings of fact or decision of the Secretary shall be reviewed by any person, tribunal, or governmental agency except as herein provided. No action against the United States, the Secretary, or any officer or employee thereof shall be brought under [§ 1331 and other specified sections] of Title 28 to recover on any claim arising under this [subchapter II of the Social Security Act].”
See Weinberger v. Salfi, 422 U. S., at 756 n. 3.
The initiating judge observed that jurisdiction for his court was asserted under the general federal-question provision of 28 U. S. C. § 1331, and under 28 U. S. C. § 1361, vesting the district courts with jurisdiction “in the nature of mandamus to compel an officer or employee of the United States or any agency thereof to perform a duty owed to the plaintiff.” Norton v. Richardson, 352 F. Supp. 596, 598 n. 2 (Md. 1972).
The Solicitor General contends that a district court has jurisdiction to review a Social Security ruling only under § 205 (g) because § 205 (h) specifically excludes any other source of review of such determinations. He then contends that, for two reasons, there was no jurisdiction here to issue an injunction under § 205 (g). First, § 205 (g) in terms specifies that a district court may enter a judgment only “affirming, modifying, or reversing the decision of the Secretary, with or without remanding the cause for a rehearing,” but does not say it may enjoin him, and, moreover, in this statutory structure an injunction is out of place. Second, although the suit was made to sound as a class action, a class action is never appropriate under § 205 (g), and in any case the class was not properly certified, inasmuch as there was no allegation that the members had even filed applications for benefits; thus there is no jurisdiction over the class aspects of the case. Weinberger v. Salfi, supra, is cited. Since only the individual claim remains, even if injunctive power were available under § 205 (g), it would not be appropriately exercised in review of a single claimant’s case.
The appellant contends in rebuttal that the “affirming, modifying, or reversing” language in § 205 (g) does not withdraw a district court’s general and inherent equity powers, including the power to enjoin, and that, in any event, jurisdiction remains, and an injunction may be issued, under the other cited statutes.
The respective jurisdictional statements for the original appeal and for the present one preserved appellant’s statutory claim along with his constitutional contention. The statutory claim, however, was not pressed in appellant’s brief in the present case, and at oral argument it explicitly was abandoned. Tr. of Oral Arg. 5-6.
In McLucas a single District Judge enjoined the enforcement of Art. 134 of the Uniform Code of Military Justice, 10 U. S. C. § 934, without convening a three-judge court. He did so because he considered the constitutional infirmity of the Article to be plain. See Bailey v. Patterson, 369 U. S. 31 (1962). On direct appeal, under 28 U. S. C. § 1252, the propriety of proceeding without a three-judge court was questioned. We observed that if a three-judge court was originally required under 28 U. S. C. § 2282, we ordinarily were bound to vacate the judgment and remand for the convening of a three-judge court. Flemming v. Nestor, 363 U. S. 603, 607 (1960); FHA v. The Darlington, Inc., 352 U. S. 977 (1957). Concluding, however, that no purpose could be served by deciding whether a three-judge court was required originally, because intervening decisions of this Court sustaining the constitutionality of Art. 134 had rendered the merits issue plainly insubstantial by the time the ease was before us, we vacated the judgment and remanded the case, directing dismissal. 421 U. S., at 32.