The ca de Bou breed, as I have told before, has its origin in the hold dogs brought by King Jaime I the Conqueror during the conquest of Majorca in 1229. Therefore, the breed is descendent from Spanish prey dogs and mastiffs and in this way the functional was the main factor of importance; in this case the hold, apart from other intrinsic qualities like bravery or faithfulness to its owner.
There is a good amount of information and quotations that makes sure the mentioned origin and it is TOTALLY FALSE that the Ca de Bou breed could be a descendent from dogs brought by English men to Menorca (not Majorca) around 1700. It is very possible that English people could discover the enormous potential of our dog and carried away specimens in order to cheer up the blood of their old Bulldog, the same happened in the Spanish mainland with other famous dogs like Lisbon, Bonhome, Alfonso or the very famous Toro.
Of course, Bulldogs have been crossed with Ca de Bestiar, but we cannot forget that exists a big enough number of these Majorcan Shepherd dogs that in their genes and in their morphology show Ca de Bou characters with wide masticators, heads wider, tough bodies and a lot of substance of bone and, as a general rule more molossus type. From my point of view, I think those crossbreeding between Bulldogs and Ca de Bestiar or Ca de Bestiar and Ca de Bou did not contribute in any positive way to the breed, except for very few specimens, and to results I refer.
Therefore, thinking that the Ca de Bou breed must own Bulldog´s characters is incorrect. For instance, muzzle must be a third of the total length of the head. The correct relationship would be 6/4: 6 for head and 4 for muzzle. This point wears that the bite is less jaw-lined, the maximum jaw-lining should be 0,7 centimetres. The ideal jaw-lining would be with contact because the hold would have a better fastening. Besides, a short muzzle impairs the general face expression, forming too much wrinkles at both sides of the muzzle.

Cranium facial axes must be parallel or lightly divergent, non convergent because it also modifies the expression, rising the truffle in an atypical way. Eyes must be big and oval, neither rounded nor slanting and the blacker, the better. Ears are pink. In repose, the end of the ears is below the eyes. Ears totally flat or excessively erect are undesirable.
This is the essence of the head, the most important region and which typifies the breed.