OSTEOLOGY. 67 



anterior fossa of the humerus. It presents many foramina, 

 and affords attachment to levator hnmeri and pectoralis 

 tra-nsversus. Externally placed to this the surface at the 

 inferior part is very rough, bounded ^posteriorly by a ridge 

 which runs upwards and backwards from the outer condyle. 

 This ridge is most prominent inferiorly, and there affords 

 attachment to extensor pedis at its lowest part, while 

 superiorly, and to the roughened surface in front of it, is 

 attached extensor metacarpi magnus ; from the inferior 

 part to the inferior prominent extremity of the humeral 

 ridge runs a hand of mixed luhite and elastic fibres which 

 gives attachment to panniculus carnosus, levator humeri, 

 and pectoralis transversus, and seems to bind down hume- 

 ralis externus in the twisted, wide, smooth groove which 

 we may trace from this around the external surface of the 

 bone bounded superiorly by the head and the line running 

 from this to the ridge, inferiorly by a much less prominent 

 roughened line winding round from the attachment of 

 subscapularis at the inner surface of the superior extremity 

 as far down as the external part of the outer condyle. 

 The lower part of the posterior surface presents two ridges 

 running upwards from the condyles of which the inner is 

 largest at its inferior extremity and runs straight upwards, 

 while the outer, at first insignificant, proceeds obliquely 

 inwards and upwards, becoming imperceptibly blended 

 with the middle third of the bone. It was the external 

 margin of this ridge we saw on the outer side of the bone. 

 Between the ridges is the supra-condyloid fossa, deepest in- 

 feriorly, which serves to accommodate the hamular process 

 of the ulna, and in the fresh subject contains some fat. 

 Inferiorly it presents an articulatory surface concave from 

 side to side continuous with that of the condyles. To 

 the upper part of the outer ridge anconeus is attached, 

 while caput parvum arises from the extreme superior part 

 of the inner ridge. From the inferior extremity of the 

 outer, flexor metacarpi externus arises, while the internal 

 ridge inferiorly gives attachment to the common originat- 

 ing tendon of perforans and perforatus, and externally is 

 rough for attachment of one head of flexor metacarpi 

 medius and flexor metacarpi internus. The rest of the 

 inferior extremity of the bone is occupied by the articula- 

 tory surface of the elbow-joint. It consists of two parts 

 or condyles. The inner condyle is much larger than the 



