With regard to the other muscles of the human shoulder, subscapularis, supraspinatus, infraspinatus, teres minor and teres major, they are also present in quadrupeds, but in a form more elongated, as the scapula has its dimensions more extended from below upwards--that is, from the glenoid cavity towards the superior or spinal border. =Subscapularis.=--This muscle occupies the subscapular fossa, from which it takes its origin, leaving free the superior part where the surface is found, to which are attached the serratus magnus and the levator anguli scapulæ. It passes towards the arm, to be inserted into the small tuberosity of the humerus. It is an adductor of the arm. The subscapularis does not offer any interest from the point of view of external form, for it is completely covered by the scapula. We speak of it, however, because we mention it in human anatomy, and that it affords us here a new opportunity of bringing into prominence the differences which exist in connection with the mobility of the shoulder. We remember that in man, when the arm is abducted, and then raised a little above the horizontal, the scapula see-saws, is separated, to a certain extent, from the thoracic cage inferiorly and externally, and that, on the superficial layer of muscles, we are then able to see in the bottom of the armpit, at the level of the deep portion of the posterior wall of the latter, a small part of the subscapularis muscle. In the animals with which we are here occupied it is not the same; for they are incapable of performing with their fore-limbs a movement analogous to that to which we have just referred, the humerus in their case being retained in contact with the trunk by the muscular masses which surround it. =Supraspinatus= (Fig. 68, 19; Fig. 70, 25; Fig. 72, 7).--This muscle, as its name indicates, occupies the supraspinous fossa--that is to say, that which, by reason of the direction of the scapula in quadrupeds, is situated in front of rather than above the spine. It arises from this fossa; and, further, from the external surface of the cartilage which prolongs the scapula upwards in solipeds and ruminants. It projects more or less beyond the supraspinous fossa in front. After passing downwards towards the humerus, it is inserted into the summit of the great tuberosity or trochiter--that is to say, to a part of this osseous prominence which represents the anterior facet of the great tuberosity of the human humerus, into which, as we know, the corresponding muscle is inserted. In solipeds and ruminants it is inserted, by a second fasciculus, into the small tuberosity. In the pig and the horse its anterior border is in relation with the terminal portion of the sterno-prescapular anterior portion of the small or deep pectoral.