[1, 2] Plaintiff assigns as error the refusal of the trial court to submit an issue as to last clear chance. To invoke that doctrine, plaintiff must plead it and the burden of proof is upon him. Exum v. Boyles, 272 N.C. 567, 158 S.E. 2d 845; Bailey v. R. R., 223 N.C, 244, 25 S.E. 2d 833. Plaintiff’s pleadings need not contain the words “last clear chance,” but to have the benefit of that issue it is necessary that facts be alleged and proof thereof offered which bring the doc*93trine into play under the circumstances of the particular case. See, Annot., 25 A.L.R. 2d 257.
 In the present case, after defendant by its answer had pleaded the defense of contributory negligence, plaintiff filed no reply. Plaintiff contends that the allegations of his complaint are sufficient to raise the issue of last clear chance, pointing particularly to paragraph 8 of the complaint. It is true that allegations and proof of “original negligence” on the part of the defendant may, under some circumstances, be sufficient to bring the doctrine of last clear chance into play, provided the other elements of that doctrine are sufficiently alleged and proved. Exum v. Boyles, supra. In the present case, however, it is questionable whether such other elements were sufficiently alleged in plaintiff’s complaint. Only by the most liberál construction of paragraph 8 of the complaint can it be said that plaintiff has alleged facts from which it may be inferred that the collision occurred when plaintiff had gotten into a position of helpless peril or had gotten into or was moving into a position of peril to which he was inadvertent, and that after defendant discovered or in the exercise of due care should have discovered plaintiff’s situation, defendant had both the time and means to avoid the injury and negligently failed to do so. We do not, however, find it necessary to pass upon the sufficiency of plaintiff’s pleading, since in our view the trial court was clearly correct in refusing to submit an issue as to last clear chance for the reason that the issue did not arise on the evidence presented.
 All of the evidence tended to show: The bus was moving west on the inside westbound lane of Highway No. 74, approaching the intersection with Walkup Avenue. The light facing the bus was green. It was moving with the other traffic at 35 to 40 miles per hour, well within the posted speed limit. While it was raining, there was no evidence from which the jury could find that the bus was traveling at an unsafe speed under the conditions then existing. When the driver first saw plaintiff, he was riding his bicycle slowly northward on Walkup Avenue and was about the center of the inside, or northern, lane of the eastbound traffic lanes on Highway No. 74. At that point the plaintiff on his bicycle had yet to travel across the remainder of the eastbound inside lane and across all of the 30-foot median before he would reach any position of peril as far as the bus was concerned. The traffic light in the center of the median facing the plaintiff was red. The bus driver, in the exercise of due care, was at that time reasonably entitled to assume that plaintiff would stop within the median. Raper v. Byrum, 265 N.C. 269, 144 S.E. 2d 38; Hawes v. Refining Co., 236 N.C. 643, 74 S.E. 2d 17. Had the plaintiff *94done so, he would have been entirely safe so far as the bus was concerned. When plaintiff continued to move slowly through the median and had reached the center thereof, the bus driver blew his horn. At that time the bus was 180 to 200 feet from the intersection and traveling at 35 to 40 miles per hour. So traveling, the bus would reach the intersection in less than four seconds. Only thereafter, when the plaintiff despite the warning signal continued to move toward a place of danger, can it be said that the bus driver in the exercise of due care should have known that plaintiff was inadvertent to his peril and might continue to move toward and into a place of danger. By that time a substantial portion of the four seconds required for the bus to reach the intersection must have elapsed. Certainly the evidence would not support a finding that the bus driver then had sufficient time remaining to take effective action to avoid the collision.
 There is. a question whether plaintiff’s evidence was sufficient to submit the first issue relative to defendant’s negligence to the jury. It is clear that it was not sufficient to require submission of an issue as to last clear chance. While the doctrine can be invoked where it is shown that the plaintiff, even though not yet in a place of peril, is negligently moving into a position of peril and is inadvertent to that fact, this is true only if the evidence also shows that when the defendant either knew, or in the exercise of due case should have known of the plaintiff’s situation, defendant still had sufficient time and the means to avoid the injury and negligently failed to do so. Here, there was no evidence that the bus driver had sufficient time remaining. There was no error in the court’s refusal to submit an issue as to last clear chance.
Plaintiff also assigns as error one portion of the judge’s charge relating to the second issue. This portion, when considered contextually with the charge as a whole, could not have misled the jury. Considered as a whole, the charge correctly declared and explained the law arising on the evidence. The court explained fully the standard of care required of a child of plaintiff’s age and experience and the rebuttable presumption that he was incapable of contributory negligence. We find no prejudicial error in the trial.
BeoCK and BRItt, JJ., concur.