Does the existence of subordinate agreements or conspiracies preclude the jury from finding an overall conspiracy?

The district judge's conclusion that the existence of subordinate agreements or conspiracies does not preclude the jury from finding the participants of those separate conspiracies guilty of an overall conspiracy, is consistent with our holding in United States v. Perry, supra. There, the defendant requested an instruction to the effect that if the jury found two or more unconnected conspiracies, it could not find the defendants in that case guilty of the conspiracy charged in the indictment. We concluded that this proposed jury instruction was an incorrect statement of the law of multiple conspiracies: