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limb, and secondly, from the alteration of the axis of action, on account 

 of the greater elevation of the basal bone in comparison with its 

 thoracic representative. Along the inferior margin of the basal bone 

 lies the fourth muscle of this series, represented in the lower limb by the 

 scansorius or gluteus quartus, and in the other extremity by the teres 

 minor. These muscles agree, first, in their insertion point being 

 typically low upon the great tuberosity ; secondly, by their relation 

 being so close to the last-mentioned pair of muscles, a third of which 

 it forms. Its human relationship long led me to entertain the mistaken 

 idea that the meso-gluteus was of the same type as the supraspinatus, 

 and the endogluteus represented the infraspinatus ; but I believe the ba- 

 lance of evidence is in favour of the arrangement as above given. One 

 thing seems clear, that the representation of the upper limb pair is 

 to be looked for in these two muscles of the gluteal series. A 

 second marginal muscle occurs on the inner edge of this lower 

 border, the iliocapsular of the lower limb, or the subscapulo hu- 

 meral of the upper, neither being constant muscles in man, al- 

 though of regular occurrence in many animals. The last of the 

 basal muscles on the inner surface of the typical bone is the subsca- 

 pularis of the upper, or the iliacus of the lower limb, and that they 

 correspond may be assumed for the following reasons : — both are com- 

 posed of fine muscular fibres; both are inserted into the smaller 

 tuberosity or trochanter ; both pass close to the capsular ligament of 

 the basal joint — indeed often having the subjacent bursa (which exists 

 under each tendon) communicating with the cavity of the joint ; both 

 have the main artery of the limb in contact with them ; both occupy 

 nearly the entire of a surface of the basal bone, which surface is on the 

 visceral aspect of that limb. Certainly in some animals the iliac 

 attachment seems to be very much everted. In the opossum I have 

 found it so, and in the Ornithorhynchus and Echidna Professor 

 Huxley and Mr. Mivart have been led to assign a different position 

 to it from this very fact ; but putting against these few cases, first, 

 the instances in which the origin of the subscapulars is marginal, as 

 in the Testudo grceca, and Hawksbill, and secondly, the arrangement 

 of the iliacus in the vast majority of animals, I think we are entitled 

 to consider that the subscapularis and iliacus are the representatives of 

 the inner marginal muscle of the columnar basal bone. 



To the ischiatic side of the basal bone lie a third or rotator group, 

 very irregularly represented in the two extremities. The chief elements 

 of this series are the pectoralis minor in the upper extremity, and the 

 obturator muscles in the lower : the obturator internus is most 

 probably represented by the pectoralis minor, as I have tried to show 

 ( 1 'Journal of Anatomy," vol. i., p. 317), and as illustrated by the pectorals 

 of the ostrich, in which the component bones of the scapular shoulder- 

 girdle are converted into a single os innominatum. The insertion of this 

 muscle into the coracoid process is but a stopping short of the obturator 

 at the lesser ischiatic notch ; and there is usually, as I have elsewhere 



