There is, accordingly, a connection to be established between those displacements which are similar and the analogy of facial expression which necessarily results from them.[33] [33] Édouard Cuyer, 'The Mimic,' Paris, 1802. =Zygomaticus Minor= (Fig. 90, 4; Figs. 91, 92).--The existence of this muscle has not been clearly demonstrated. Nevertheless, Straus-Durckheim noted its presence in the horse, and described it as 'a muscle arising by two heads, of which one, the superior, arises from the malar bone below the orbit, and passes downwards and forwards over the fibro-adipose layer which supports the moustache. The second, the inferior, arises from the alveolar border in front of the second molar tooth, and passes forward to be inserted into the same fibro-adipose layer.'[34] [34] H. Straus-Durckheim, 'Anatomie descriptive et comparative du chat,' Paris, 1845, t. ii., p. 210. In connection with other quadrupeds, it is described by certain authors as a very thin muscle, arising below the cavity of the orbit, where it is blended with the fibres of the internal elevator of the upper lip and the ala of the nose; thence it proceeds to terminate below by uniting with the subcutaneous muscle. But this muscle is regarded by other authors as the lachrymal muscle, which does not exist in this state in man, but of which the development is particularly remarkable, as to extent, in the ox, in which it descends as far as the buccinator. According to other authors, some of the fibres of this muscle constitute the small zygomatic. [Illustration: FIG. 91.--MYOLOGY OF THE OX: MUSCLES OF THE HEAD. 1, Masseter; 2, orbicularis palpebrarum; F, frontalis; 3, zygomaticus major; 4, lachrymal (this muscle is sometimes described under the name of small zygomatic); 5, levator labii superioris proprius; 6, levator labii superioris alæque nasi; 7, levator anguli oris or caninus; 8, orbicularis oris; 9, buccinator; 10, maxillo-labial; 11, zygomatico-auricularis; 12, external temporo-auricularis; 14, parotid gland; 15, parotido-auricularis; 16, inferior maxillary bone.] =Levator Labii Superioris Proprius= (Fig. 90, 5; Figs. 91, 92).--Also named by veterinarians the _supramaxillo-labial_, or again, the _proper elevator of the upper lip_, this muscle arises from the external surface of the superior maxillary bone, passes under the superficial elevator, which we shall study in the succeeding paragraph, and goes to be inserted into the thickness of the lip, to which its name indicates that it belongs. The peculiarities of this muscle in different animals are the following: In the dog and the cat it arises behind the infra-orbital foramen. In the pig it arises from a depression below the orbital cavity, and its fleshy body is terminated in front by a strong tendon in the upper part of the snout, in which it divides into fasciculi. In the ox it arises from the maxillary spine.