Defendant asserts as a defense that he was insane at the time of the commission of the crimes charged in the bills of indictment and at the time of trial. He contends that the trial court erred in finding him competent to stand trial, and that it again erred in failing to grant his motion for nonsuit on the ground of insanity.
[1, 2] Incapacity to stand trial and insanity as a defense to a criminal prosecution are two different concepts. Whether a defendant is competent to stand trial depends on his mental condition at the time of trial. “ Tn determining a defendant’s capacity *295to stand trial, the test is whether he has the capacity to comprehend his position, to understand the nature and object of the proceedings against him, to conduct his defense in a rational manner, and to cooperate with his counsel to the end that any available defense may be interposed.’ ” State v. Jones, 278 N.C. 259, 266, 179 S.E. 2d 433, 438; State v. Propst, 274 N.C. 62, 70, 161 S.E. 2d 560, 566; accord, State v. Lewis, 11 N.C. App. 226, 181 S.E. 2d 163, cert. denied, 279 N.C. 350, 182 S.E. 2d 583. Whether a defendant can be held responsible for his illegal act depends on his mental condition at the time the act was committed. “In this state, the test of insanity as a defense to an alleged criminal offense is the capacity of the defendant to distinguish between right and wrong at the time of and in respect of the matter under investigation.” State v. Atkinson, 275 N.C. 288, 313-14, 167 S.E. 2d 241, 256; accord, State v. Humphrey, 283 N.C. 570, 196 S.E. 2d 516; State v. Spence, 271 N. C. 23, 155 S.E. 2d 802, aff’d mem., 392 U.S. 649.
[3] Dr. Eugene V. Maynard, an expert psychiatrist who treated defendant at Cherry Hospital, testified about defendant’s mental condition at the hearing on his competency to stand trial, and again during the trial as a witness for defendant. He stated that in his opinion defendant had known the difference between right and wrong at the time of the robbery on 29 December 1972; that when defendant was admitted to Cherry Hospital on February 6, he was suffering from paranoid schizophrenia, a psychotic condition, possibly brought on by the shock of being arrested and jailed; that a drug known as Haldol had been prescribed for defendant at Cherry Hospital; that the drug had brought about a remission in defendant’s psychotic condition; and that defendant was now competent to stand trial. In addition to the testimony of Dr. Maynard, Dallas M. Hall and Jack Horrell, the two eyewitnesses to the crime, testified that defendant did not appear to be insane at the time of the robbery. This testimony clearly constitutes competent and substantial evidence in support of the trial court’s finding that defendant was competent for trial and its denial of defendant’s motion for non-suit. The court did not err in either of these rulings.
[4] Defendant objects to several of the court’s rulings on the admission and exclusion of evidence. First, he contends that the court should not have admitted into evidence the five photographs shown to Hall and Horrell, one of which they identified as a photograph of defendant. This contention is without merit. *296“A witness may use a . . . photograph ... to illustrate his testimony and make it more intelligible to the court and jury.” 1 Stansbury, N. C. Evidence (Brandis rev.), § 34, at 93-94; accord, State v. Johnson, 280 N.C. 281, 185 S.E. 2d 698; State v. Preston, 9 N.C. App. 71, 175 S.E. 2d 705.
[5] Defendant also argues that the court erred in failing to permit him to cross-examine Dr. Maynard, who was called as a defense witness but gave testimony that was damaging to defendant. The trial judge may in his discretion allow a party to cross-examine his own witness, State v. Tilley, 239 N.C. 245, 79 S.E. 2d 473; State v. Vicks, 223 N.C. 384, 26 S.E. 2d 873, but only upon request. Here defendant never requested permission to cross-examine Dr. Maynard. In any event the opinion of Dr. Maynard and the information and study of defendant upon which it was based were all in the record of his testimony on direct examination.
[6] Several of defendant’s exceptions relate to the court’s charge to the jury. One of these has to do with the instructions on the burden of proof. There is no set formula that must be used in charging on the burden of proof, and the instructions given in this case clearly indicated to the jury that the State must prove defendant guilty beyond a reasonable doubt and were entirely proper. State v. Glatly, 230 N.C. 177, 52 S.E. 2d 277; State v. Ray, 209 N.C. 772, 184 S.E. 836.
[7] The court instructed the jury accurately on defendant’s failure to testify. State v. McNeill, 229 N.C. 377, 49 S.E. 2d 733; State v. Artis, 9 N.C. App. 46, 175 S.E. 2d 301. When the defendant does not request an instruction on his failure to testify, it is better for the court not to give any charge on this subject; but the giving of an unrequested instruction does not constitute error, if it correctly states the law. See State v. Barbour, 278 N.C. 449, 180 S.E. 2d 115, cert. denied, 404 U.S. 1023.
Defendant contends that the trial judge summarized Dr. Maynard’s testimony too briefly. However, the court’s discussion of the evidence given by Dr. Maynard takes up 1% pages of the record and mentions the most important parts of his testimony. It is not necessary and indeed it would be impossible for the judge to restate everything a witness has said. The court must of necessity give the witness’s testimony in a shortened, summarized form. Steelman v. Benfield, 228 N.C. 651, 46 S.E. 2d 829.
*297 [8, 9] Defendant asserts that the court failed to instruct the jury on “felonious intent,” one'of the elements of the crime of armed robbery. “An essential element in robbery cases ‘is a “felonious taking,” i.e., a taking with the felonious intent on the part of the taker to deprive the owner of his property permanently and to convert it to the use of the taker.’ ” State v. Mundy, 265 N.C. 528, 530, 144 S.E. 2d 572, 574. In every armed robbery case the court must instruct the jury on this element of the crime. Id. But the judge does not have to use the specific words “felonious intent”; he is only required to give a correct description of the state of mind necessary for the crime. State v. Spratt, 265 N.C. 524, 144 S.E. 2d 569. In this case the court instructed the jury that in order to convict defendant, they must find that at the time he took the property of Dallas M. Hall and Jack Horrell, he “intended to deprive them of its use permanently . . . [and] knew that he was not entitled to take the property.” This is an accurate description of the “felonious intent” necessary for armed robbery, and it meets the requirements of the Mundy and Spratt cases.
The court properly instructed the jury on the issue of insanity. State v. Lamm, 232 N.C. 402, 61 S.E. 2d 188.
Defendant has received a fair trial free from any prejudicial error.
No error.
Judges Parker and Hedrick concur.