Defendant’s first contention is that the court erred in permitting a forensic chemist to testify for the State that in his opinion the vegetable matter defendant was charged with selling was marijuana. The basis of this contention is the trial court’s *636failure to enter a finding in the record that the witness was an expert and qualified to express an opinion. There was plenary-evidence tending to show that the witness was an expert in the field of chemistry and that he possessed appropriate qualifications to give his opinion that the substance in question was marijuana. He testified that his opinion was based on a microscopic visual examination of the substance and two separate tests which he performed. Defendant did not object to any of the witness’s testimony; nor did he request the court to enter findings as to the qualification of the witness as an expert. Under these circumstances, it was not necessary that the trial judge enter findings in the record relating to the witness’s qualifications before allowing him to express his opinion. State v. Perry, 275 N.C. 565, 169 S.E. 2d 839; State v. Johnson, 13 N.C. App. 323, 185 S.E. 2d 423; Stansbury, N. C. Evidence 2d, § 133.

Defendant’s remaining contention is that the court committed error in failing to define the term “reasonable doubt.” It is well settled in this jurisdiction that the failure of a trial judge to define the term “reasonable doubt,” absent a request, that he do so, is not reversible error. State v. Potts, 266 N.C. 117, 145 S.E. 2d 307; State v. Browder, 252 N.C. 35, 112 S.E. 2d 728; State v. Lee, 248 N.C. 327, 103 S.E. 2d 295.

Defendant’s counsel candidly concedes that the law presently prevailing in this jurisdiction does not support either of his contentions. We have examined his forceful argument that new rules should be formulated. Even if this Court had the authority to do so, which it does not, we would not be inclined to disturb the well established principles applicable to the contentions raised on this appeal.

No error.