505. Surety's right of proof against co-sureties.

A surety has a right of proof against a co-surety for a just proportion of the debt when he has paid the creditor's debt and taken an assignment of his securities1; and, even if he has not paid the creditor, and his liability has not been ascertained, he will have a right to a declaration that, when he has paid more than his due proportion, the co-surety must contribute, and in respect of that right he will be entitled to prove against the co-surety's estate