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this situation is so thin that it needs no special muscular tensor, and we 

 would have the condition of this muscle similar in both limbs. 



From the ischiatie segment of the basal bone in each limb we have 

 another series of muscles, the adductors — muscles truly femoral in man, 

 but degraded to the tibia in the seal, forming an illustration of a 

 principle commonly to be noticed in anatomy, that when a muscle loses 

 its special individuality of action, its insertion becomes degraded, or 

 extended to more than one bone or segment of the extremity. This 

 group is represented usually by rive elements, well developed in the 

 lower limb of man, these are : one, basio-tibial, the gracilis, represented 

 in the upper limb of man by the chondro-epitrochlearis, a slip from the 

 cartilage of the seventh or eighth rib to the inner condyle of the 

 humerus, and inner intermuscular septum : the second element, or the 

 great adductor portion, extends from the tuber ischii (coracoid process) 

 to the primal limb bone, and is represented in the thigh by the adductor 

 magiras — in the arm. by the portion of the coraco-brachialis overlying 

 the musculo-cutaneous nerve. These parts agree, first, because they 

 are inserted the nearest to the flexor aspect of the limb, and in contact 

 with the flexor muscle ; secondly, because this portion of the coraco- 

 brachialis extends the farthest down the limb — I have seen it extend- 

 ing as far as the epitrochlea ; thirdly, because it is most closely in 

 connexion with the main artery of the limb as a deep relation, as is 

 the adductor magnus to the femoral. The third portion of the adductor 

 mass, or pectineus. is a muscle whose fore limb representative is very 

 difficult of determination, its typical origin we find to be from the 

 pubis, and its insertion the ridge below the lesser tuberosity. Now, 

 in this position precisely we find the small muscle described by ~Kr. 

 Wood as the coraco-capsular — considered by him as a representative of 

 the adductor brevis ; but the reasons which lead me to associate it with 

 the pectineus as a representative of the same type are the following : 

 first, because its origin is the point the nearest possible to the sup- 

 pressed pubis ; secondly, its insertion is exactly typical, viz., to the 

 ridge below the lesser tuberosity ; thirdly, its relationship to the inner 

 rotator, or subscapularis, which is exactly that of the pectineus and 

 iliacus : in all these respects the coraco-capsular seems a very clear 

 homotype of the pectineus, and it leaves the coraco-brachialis proprius 

 to act as the representative of the remaining part of the true adductor 

 mass, which in many animals is condensed into one muscle. The subner- 

 vous portion I have found divided into two parts on several occasions — 

 one attached to a tendinous sling figured by Henle, immediately behind 

 the nerve, and a third more posterior, which I have found perfectly 

 separate and close to the inner head of the triceps ; these are the re- 

 presentative of the same type as the adductor brevis ; the adductor lon- 

 gus is represented by the great pectoral muscle. 



The muscles of the mesial joints are much more definite and easily 

 understood ; they are arranged into two groups, an extensor and a flexor 

 series : the former are sometimes conjoined into one mass as in the 

 but sometimes exhibit four or five individual parts per- 



