I. In every charge of violation of any speed regulation in this chapter the complaint shall set forth the manner in which the alleged speed was unreasonable and imprudent or shall specify the speed at which the defendant is alleged to have driven and the prima facie speed applicable within the district or at the location.
II. The provision of this chapter declaring prima facie speed limitations shall not be construed to relieve the plaintiff in any action from the burden of proving negligence on the part of the defendant as the proximate cause of an accident.