The trial court’s election not to submit to the jury the charge of speeding will be treated as the equivalent of a verdict of not guilty on that count. See S. v. Sorrell, 98 N.C. 738, 4 S.E. 630; S. v. Murphy, 235 N.C. 503, 70 S.E. 2d 498.
The defendant insists that since the State’s case on the charge of manslaughter rested entirely upon evidence of speeding and reckless driving as the ingredients of culpable negligence causing the death of Jesse Wyatt, the elimination at the nonsuit level of these specific charges removed from the case the elements of culpable negligence necessary to support a conviction of involuntary manslaughter, and that the court erred in refusing to allow the motion for nonsuit on the homicide count. The contention is without merit, and the assignment of error relating thereto is overruled on authority of the decision in S. v. Midgett, 214 N.C. 107, 198 S.E. 613. The decision in S. v. Rawlings, 191 N.C. 265, 131 S.E. 632, cited and relied on by the defendant, is distinguishable. The evidence on which the State relies was sufficient to carry the case to the jury on the homicide count. The motion for judgment as of nonsuit was properly overruled.
However, we are constrained to the view that the defendant is entitled to a new trial for error in the charge.
The court in charging the jury said: “. . . but if you find, gentlemen, that ... he was operating it (his automobile) carelessly and heedlessly in a wilful or wanton disregard of the rights and safety of others, and you find it was accompanied with such carelessness, or probably consequences of a dangerous nature when tested by the rules of reasonable prevision amounting to a thoughtless indifference to consequences or a heedless indifference to the rights and safety of others upon the highways, and if you find those facts, gentlemen, and all of them beyond a reasonable doubt, it would be your duty to return a verdict of guilty.”
The foregoing formula is incomplete and erroneous, in that it does not contain the element of proximate cause as an essential ingredient of culpable negligence justifying conviction of involuntary manslaughter. Here, the court was instructing the jury on reckless driving (G.S. 20-140) as a possible element of culpable negligence. It may be conceded that the state of facts included in the formula used by the court was sufficient to justify a finding that the defendant was guilty of reckless driving. But in order to justify a conviction of involuntary *153manslaughter based on the facts contained in the court’s formula given to the jury, constituting reckless driving, it was necessary that the jury go further and find beyond a reasonable doubt that such reckless driving was the proximate cause of the wreck and resultant death of the deceased Jesse Wyatt. S. v. Phelps, 242 N.C. 540, 89 S.E. 2d 132; S. v. Wooten, 228 N.C. 628, 46 S.E. 2d 868; S. v. Cope, 204 N.C. 28, 167 S.E. 456. The challenged instruction did not require the jury to find this essential element of proximate cause. The instruction given by the court authorized the jury to convict of manslaughter upon a mere finding beyond a reasonable doubt of the facts embraced in the court’s formula, constituting reckless driving, without any finding whatsoever in respect to the causal connection between such reckless driving and the death of Wyatt. This failure to instruct as to causal connection may not be treated as harmless error, particularly so in view of (1) the defendant’s testimony that he fell asleep at the wheel while driving not more than 50 or 55 miles per hour, and (2) the failure of the court to instruct the jury on the law governing criminal liability for death or injury caused by the operator of a motor vehicle falling asleep at the wheel. As to this, the mere fact that the operator of a motor vehicle involuntarily goes to sleep while operating his automobile does not, nothing else appearing, constitute culpable negligence. In determining the question of culpable negligence, the focal point of inquiry is whether the operator, because of drowsiness, previous tiring activities, or other premonitory symptoms of sleep, became aware of the likelihood of falling asleep, but nevertheless continued to operate the vehicle under circumstances evincing a thoughtless disregard of consequences or a heedless indifference to the rights and safety of others upon the highway, proximately resulting in injury or death. See S. v. Cope, supra; People v. Robinson, 253 Mich. 507, 235 N.W. 236; Johnson v. State, 148 Fla. 510, 4 So. 2d 671. See also Baird v. Baird, 223 N.C. 730, 28 S.E. 2d 225; Annotation: 28 A.L.R. 2d 12, 72.