Appellant was tried on three different charges for violations of the uniform narcotic drug law: unlawful possession of narcotic drug; forgery of prescription for narcotic drug and uttering forged prescription for narcotic drug. A jury found him guilty of only one of the charges, i. e., uttering a forged prescription for a narcotic drug in violation of § 398.19(4), F.S.A., and not guilty of the other charges. This appeal is from the judgment and sentence of two years in the state penitentiary.

One of the points urged by appellant for .reversal is: that the trial judge erred in permitting a police officer to testify over objection, that in his opinion certain scratch marks found on the defendant’s arms at the *80time of his arrest were the result of the use of heroin. We find merit in appellant’s contention and reverse.

This testimony was irrelevant to the cause and clearly prejudicial to the rights of the defendant.1 Accordingly the judgment and sentence appealed is reversed and the cause remanded for a new trial.

Reversed and remanded.