48 THE ANATOMY OF VEKTEBKATED ANIMALS. 



major, passing from ])osterior dorsal or lumbar vertebrae — tlie 

 pt/r{formis from sacral vertebras — the femoro-coccygeus (when 

 it exists) from caudal vertebire — to the femur, are all hj^po- 

 skeletal muscles, without homologues in the anterior extremity. 

 All the other muscles of the limbs are intrinsic, taking 

 their origins from the pectoral or pelvic arches, or from some 

 of the more proximal segments of the limb-skeleton, and hav- 

 ing their insertion in the more distal segments. They are 

 thus arranged in Man and the higher Manunialia : 



Intrinsic inuadcs proceeding from the pectoral or pelvic 

 arches to the humerus or femur, on the dorsal asp)ect. — In the 

 fore-limb, the deltoides proceeds frc-m the clavicle and scapula 

 to the humerus. This superficial shouldei-muscle continues 

 the direction of the fibres of the trapezius ; and, when the 

 clavicle is rudimentary, the adjacent portions of the two mus- 

 cles coalesce into a cepihalo-humeralis muscle. Beneath the 

 deltoid the svvra-spinatus, on the pre-axial side of the spine 

 of the scapula ; the infra-sp)inatx(s, and the teres major and 

 minor, on its post-axial side, run from the dorsal aspect of the 

 scapula to that of the head of the humerus. 



In the hind-limb, the tensor vaginal femoris, which passes 

 from that part of the ilium which corresponds with the spine 

 and acromion of the scapula, to the femur, appears to answer 

 better to the deltoid than does the f/liitajus ma.vimv.s, which, 

 at first sight, would seem to be the homologue of that muscie. 

 The iliacus, proceeding from the inner surface of the crest 

 of the ilium to the smaller trochanter, answers to the supra- 

 spinatus ; the glutmus tnedius and minimus, which arise from 

 the outer surface of the ilium, to the infra-spinatxis and teres. 

 In the fore-limb, a muscle, the subscaptdaris, is attached 

 to the inner face of the scapula, and is inserted into the hu- 

 merus. No muscle exactly corresponding with this appears 

 to exist in the hind-limb. 



On the ventral aspect in the fore-limb, the coracohrachialis 

 passes from the coracoid to the humerus. In th-e hind-limb, a 

 number of muscles proceed from the corresponding (ischio- 

 pubic) part of the pelvic arch to the femur. These are, from 

 the outer surface of the pubis, the jxctiiieus, and the great ab- 

 ductors oi the femur; with the obturator externus, from the 

 outer side of the ischiopubic fontanelle, or obturator membrane. 

 The gemelli and the qitadratus femoris take their origin fiom 

 the ischium. 



No muscle is attached to the proper inner surface of the 

 ilium, so that there is no homologue of the subscaptdaris in 



