The 'superior maxillaries' here swell into importance, and constitute the whole of the outer wall, and, sometimes, a part of the roof. The jaws are the weapons of offence and defence; and as much space as possible is devoted to the insertion of those muscles that will enable the animal to seize and to hold his prey. One of the most powerful of them, the 'masseter', rises from the superior maxillary bone, and spreads over its whole extent: therefore, that bone is developed, while the nasal bone is compressed into a very small space. The substitution of a portion of cartilage, instead of bone, at the posterior part of the orbital ring, in order to give more play for the coracoid process of the posterior maxillary, round which the temporal bone is wrapped, is a contrivance of the same nature. The scent of the dog is not sacrificed or impaired by the apparent diminution of the nasals; for the cavity enlarges considerably upward, and is occupied chiefly by the 'ethmoid bone', which, having the greater portion of nervous pulp spread on it, seems to have most to do with the sense of smell. The nasal bones of the dog are essentially different from those of the horse, cattle, and sheep. They commence, indeed, as high up in the face as those of the horse, their superior extremities being opposite to the lachrymal gland; but that commencement is an apex or point varying materially in different breeds. They form, altogether, one sharp projection, and are received within breeds these processes extend nearly one-third of the length of the nasals. The superior maxillary (3.3.) takes the situation of the nasal (2.), pushes the lachrymal bone (4.) out of its place, and almost annihilates it, reaches the frontal bone (7.) and expands upon it, and forms with it the same denticulated suture which is to be seen in the nasal. The action of the muscle between these bones, and for the development of which all this sacrifice is made, is exceedingly powerful. The strength of this muscle in a large dog is almost incredible: the sutures between these bones must possess corresponding strength; and so strong is the union between them, that, in many old dogs, the suture between the superior maxillary and frontal bones is nearly obliterated, and that between the nasal and frontal maxillary quite effaced.