This brought a new fashion to the Toy Spaniel - dogs with the completely flat face, undershot jaw, domed skull with long, low set ears and large, round frontal eyes of the modern King Charles Spaniel (also called «Charlies» and known in the United States today as the English Toy Spaniel). (ckcsc.org)
Acrotholus walked on two legs and had a greatly thickened, domed skull above its eyes, which was used for display to other members of its species, and may have also been used in head - butting contests. (sciencedaily.com)
It was smaller, with a more profuse coat, a shorter head, and a more domed skull, than its English cousin. (akc.org)