MEMBRAL LANDMARKS. 97 



§ 229. Zygoma — The Arcus zygomaticus— (Fig. 30, 56). — Both 

 the dorsal and ventral borders of this may usually be felt distinctly, 

 although in old males it is more or less obscured by the thickness 

 of the skin and connective tissue upon the cheeks. The dorsal 

 border is nearly in line vrith the lateral angle of the eye. 



Dlapophysis atlantalis — Transverse process of the atlas verte- 

 bra — (Fig. 30, 62). — This may be felt as a ridge just caudad of the 

 base of the ear. The caudal angle is more distinct, and the soft 

 parts on its ventral side are less prominent and firm than those upon 

 tlie dorsal. 



Scapula — (Fig. 30, 44). — The middle of the convex vertebral 

 margin of the scapula projects dorsad of the intervening cervical 

 neural spines, so as to give rise to the Depressio inter scapular is 

 which is so marked while the living cat is on its feet. Upon a lean 

 animal, the following scapular prominences may be easily deter- 

 mined : mesoscapula, with its tuberosity (Fig. 44) ; gleno-vertebral 

 angle (Fig. 48) ; (the coraco-vertebral angle is so heavily overlaid 

 with muscle as to be less easily felt) ; acromion (Fig. 44, 45) ; 

 metacromion. 



§ 230. Costa iJ— Last rib. — The abdominal parietes just caudad 

 of the last rib are easily indented by the finger almost to the apex 

 of the triangular area which intervenes between it and the lateral 

 border of the vertebral muscles (Fig. 30). 



Crista ilii. — When the finger is carried along the border of the 

 vertebral muscles at about the same distance from the meson as the 

 apex of the angle between them and the last rib, the Crista ilii is 

 felt as a rounded ridge nearly dorsad of the knee (Fig. 51). 



Tuberositas ischii — Ischiatic tuberosity. — This is felt as a blunt 

 prominence ventro-laterad of the anus. 



Olamcula — The clavicle or collar bone — (Fig. 30, 48, 67, 72). — In 

 young or lean animals this may be felt by pinching up the skin 

 and subjacent muscles between the shoulder and the prsesternum. 



Membra! Iiandmarks. — These, likewise, are in pairs, but are 

 spoken of in the singular number. 



§ 231. Arthra. — After what has been said in the general descrip- 

 tion of the skeleton (§§ 214-223), there wiU be no difiiculty in ascer- 

 taining the position of any of the membral arthra. Most of the 

 bony prominences also may be recognized readily from their rela- 

 tions to the ai'thra. 



TrocMter — (Fig. 30, 46) — The greater tuberosity of the humerus. — 

 7 



