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muscles were still represented by the typical greater tuberosity ones ■ 

 thirdly, because the muscle correspondences based upon this theory are 

 by no means as striking as those to be ascertained by the acceptance of 

 the fifth theory, which, with little modification, we will find to be the 

 most suitable, and the one most clearly in accordance with the com- 

 parisons about to be instituted. The theory I would wish to propose 

 is this-— the basal bone of the limb I believe, with Mr. Mivart, to be 

 typically a columnar organ with muscles placed along its four sides ; 

 this is modified by the projection and lamination of its angles, or by its 

 occasional flattening into a flat surface, a change that is accomplished 

 by the great elongation of the two edges and the flattening and obso- 

 lescence of the others: thus the basal segment may present us with an 

 outer and inner side, as we find in both limbs in man ; in the thoracic 

 limb having its upper surface represented by the supraspinous fossa, and 

 its outer by the infraspinous ; its lower by the axillary costa, and its 

 inner by the subscapular fossa. In the pelvic member we find these 

 surfaces represented — the upper by the portion of the ilium below the 

 middle curved line, the external, by the space intervening between the 

 middle line and the crest of the ilium; the inferior, by the anterior iliac 

 margin, and the internal, by the iliac fossa. Thus most of the muscular 

 and bony points of the upper part of the limb I believe correspond in 

 the manner pointed out by Professor Humphry ("Human Skeleton," p. 

 599, and " On the Limbs of Vertebrate Animals"). The femur and 

 humerus I believe correspond to the one type ; the greater and lesser 

 trochanters to the greater and lesser tuberosities respectively ; and at the 

 lower end, as the head of the fibula does not come in contact with the 

 lower end of the femur, the capitulum humeri is not represented at 

 all upon the latter bone ; and the two sides of the trochlea correspond 

 to the two condyles of the femur. In this latter point there is a slight dif- 

 ference in the theoretic arrangement which I would here propose from 

 Dr. Humphry's comparison. When we compare the bones of the foreleg, 

 we find that the fibula and tibia present us with some points of diver- 

 gence from the forearm bones, or radius and ulna. Comparing the bones 

 at the upper ginglymus articulation, we find that the tibial element in 

 the one case taken with the patella represents the ulnar element in the 

 upper limb taken in common with the olecranon ; and the fibular head 

 is the representative of the upper extremity of the radius, its articular sur- 

 face diminished because its action is lost, and its tubercle elongated, be- 

 cause required for the insertion of the outer flexor ; but when we compare 

 the terminal segments of the limbs, we find that to homologate properly 

 the hand and the foot, we require to rotate the segment, so that the thumb 

 orpolliceal edge of the hand and the halluceal edge of the foot will both 

 point forwards. Now, in doing this, it will be noticed that the radius 

 will be brought forward, taking the place in the upper limb which is 

 occupied by the tibia in the lower. If we examine these bones as they 

 are placed in the foreleg of the elephant, we will there see that to 

 homologate the fore and hind foot, a permanent state of crossing or 

 pronation is required, and thus we can explain the apparent discrepancy 



