OSTEOLOGY OF LAEID^. 599 



is, however, merely the apposition of the extreme tip of the bone with the inner aide 

 of the head of the scapula. There is a well developed tubercle and articulating facet 

 for the head of the coraeoid. The bones are not connected except ligamentously with 

 the sternum. Thev unite at about the same angle, and have much the same amount 

 of longitudinal curvature in all the subfamilies. The symphysis is perhaps a little 

 broader and stronger in the ii^/ridiiifr than in the others. There is a well developed 

 projecting process at the symphysis, most marked in the Vtt)-nincc. The bones curve 

 greatly downward and backward toward the sternum, and then approach each other 

 with a still greater amount of inclination; so that while the angle the shafts of the 

 bone make with each other is small, the real angle of the union of the two is very 

 obtuse. This gives the bones the ^ellui^>ite amount of power in preventing the ap- 

 proximation of the heads of the coracoids. 



Hl^^rERUS. — This hone presents several interesting features. The superior or anterior 

 crest is short but very high ; it rises abruptly from the shaft, and from the upper ex- 

 tremity of the head of the bone, with perfectly plane, smooth sides The inferior or pos- 

 terior crest, on the other hand, is broadly convex both longitudinally and transversely on 

 its outer aspect ; its longitudinal convexity gives the head of the bone nearly all of its 

 obliquity with reference to the axis of the shaft. It arches over the posterior aspect 

 of the end of the shaft, this vaulting being formed by a deep excavation or concavity 

 on its posterior aspect. This excavation is complete and open in Lariiicc and Stemini, 

 and is divided in two by a prominent longitudinal ridge ; while in the Leittridince the 

 excavation is partially closed in by a plane prolongation of the shaft, which leaves 

 only a rather small oval foramen to open into the excavation. The apes of the crest 

 has a considerable prolongation backward, separated from the articularhcad by a deep 

 notch. Its convex siiriace is marked near the head of the bone by two deep grooves, 

 one parallel with, the other perpendicular to, the axis of the shaft. The articular head 

 of the bone is narrowly oval, but very convex, its long axis lying between the extrem- 

 ities of the two crests. A prominent ridge of bone arises from the shaft, and runs up 

 between the two crests to the head. The greater part of the expansion about the head 

 of the bone is rough, for the attachment of ligaments and tendons. 



The most notable feature of the lower extremity of the bone is the presence on its 

 outer edge, just above the radial tubercle, of a prominent, well developed, acnte "sty- 

 loid" process. This projects directly from the side of the bone, and at right angles 

 with it. It serves for the origin of the tendon of the extensor carpi radialis longior. 

 On the opposite side of the bone, jnst above the ulnar tubercle, there is a slight promi- 

 nence, but nothing deserving the name of a process. I have observed none of the sup- 

 plementary bones lately described by Prof, Keinhardt as occurring in a majority of the 

 ProceUariUla:, and do not think any such exist. 



The elongation and obliquity of the radial facet are well marked, but present nothing 

 unusual in shape or size, as is the case with the rounded ulnar tubercle. There is a 

 very large and deep ccronoid fossa on the anterior aspect of the bone just above the 

 condyles, most extensive in the Larinof, shallowest in the Lestridina;. There is no 

 olecranoid depression, but in place of it the extremity of the bone posteriorly pre- 

 sents a deep longitudinal groove on the ulnar side, which condncts the extensor tendon. 

 This groove is bounded internally by a well developed ulnar condyle ; extemallv bv 

 a slight ridge, which separates it from a narrow, shallow groove that runs over the 

 radisS side of the extremity of the bone. 



Bo^"ES oy the foreaem, — The ulna is considerably longer than the humerus, and 

 very stont and strong. It is considerably curved on its axis, the convexity presentino- 

 backward. Its posterior aspect is marked with two or three rows of slight ronchened 

 eminences, denoting the attachment of feathers. The head is large and stout, its artic- 

 ulating facets presenting forward. The inner of these is a perfectly circular cup-shaped 

 depression, the anterior margin of which forms what there is of a coronoid process. 

 while a considerable projection posteriorly to it constitutes the olecranon. Just beside 

 this facet there is on the radial side of the head of the bone the smooth concavo-convex 

 depression, which forms, together with the head of the radius, the elongated oblique 

 facet for articulation with the radial tubercle of the humerus. The distal extremity 

 of the bone presents the usual curved surface on its radial aspect, over which the ex- 

 panded and deflected extremity of the radius is applied. Below and posterior to this 

 is an elongated, smooth, Ifcngitudinally convex and transversely concave trochlea.' 

 surface. 



The radius is, as usual, very slender and cylindrical. Its head is rather oval than 

 round, but its facet is nearly circular. Its distal extremity is laterally expanded and 

 deflected, to overlie the extremity of the ulna. It is marked with a slight loniritudinal 

 groove along which plays the tendon of the extensor. ° 



The radio-carpal bone is comparatively very small, being much less than the "pisi- 

 form." It is of an indescribably irregular fonn. It has three smooth articulating sur- 

 faces; a deep, oval transverse one for the raditis ; a very small, shallow one besfde it 

 for the ulna ; and on the opposite side a larger, somewhat crescentic, concavo-convex 



