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OSTEOLOGY OF LAEID^. 599 



is, however, merely the apiiositiou of the extrenip tip of the bone with the inuer side 

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

 for the head of the coracoid. The bones are not connected except ligauicutously with 

 the steruuui. They unite at about the same angle, and have much the same amount 

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

 broader and stronger in the Lcsfridina' tliau in the others. Tliere is a well developed 

 projecting process at the symphysis, most marked in the fSteniinw. The boues curve 

 greatly downward and backwarcl toward the sternum, and theu 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 requisite amount of power in preventing the ap- 

 proximation of the heads of the coracoids. 



Humerus. — This bone presents several interesting features. The superior or anterior 

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

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

 terior crest, on the other hand, is broadly convex both longitudinally and ti-ansversely on 

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

 obliquity -uitli 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 aud open in Lavina', and Sterninai, 

 aud is divided in two by a prominent longitudinal ridge; while in the Lcstridince 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 apex of the crest 

 has a considerable prolongation backward, separated from the articular head by a deep 

 notch. Its convex snri'ace 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 lione 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, acute "sty- 

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

 with it. It serves for the origin of the ttmdon of the extensor carpi radial'is longior. 

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

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

 plementary boues latelj- described by Prof. Eeinhardt as occurring in a majority of the 

 Froccllariida; and do not think any such exist. 



Tlie elongation and obliquity of the radial facet are well marked, but preseut 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 boue just above the 

 condyles, most extensive in the Larhia; shallowest in the Lestrldinw. There is no 

 olecranoid depression, but in place of it the extremity of the bone posteriorly i)re- 

 sents a deep longitudinal groove on the ulnar side, which conducts tlu3 extensor tendou. 

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

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

 radidS side of the extremity of the bone. 



BoNK.s Of THE I'oitEAKM. — TIic ulua is considerably longer than the humerus, and 

 very stout and strong. It is considerably curved on its axis, tlie convexity inescnting 

 backward. Its posttsrior aspect is marked with two or three rows of sliglit roughened 

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

 ulating facets juescnting forward. The inuer of these is a perfectly circular cu[)-shaped 

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

 while a considerable projection ])osteriorly to it constitutes the olecranon. Just beside 

 this fact't there is on the ra<lial side; of the head of the bone the smooth concavo-convex 

 depression, wliich forms, togetlier witli tlie Iiead of the radius, the elongated ohlii|UO 

 iacet foi- articulation with tlie radial tubercle of the humerus. Tlie distal extremity 

 i>t' tlie bone ])reseiits tlie usual curved siirtaci; on its radial asj)ect, over which the ex- 

 jianded and delleeted extremity of tiu' radius is api)lie(I. IJelow and posterior to tliis 

 is an elongated, smooth, longitudinally convex aud transversely concave trochlea." 

 surface. 



Th<! radius is, as usual, very .slender and cylindrical. Its head is rather oval than 

 round, Imt its facet is nearly circular. Its distal extremity is laterally exi)anded and 

 ilellected, tooveilie tlie extremity of the ulua. It is marked witli a slight longitudinal 

 gi'oove along wliieli plays the tendon of the extensor. 



The radio-eari)al lioiu^ is lonqjaiat i\ fly very small, being niiieh less th;in the ''pisi- 

 form." It isot'an indescribably irregular form. It has three smooth articulating sur- 

 faces; u deep, oval transverse one for the radius ; a very small, shallow one beside it 

 for ttie ulna ; and on the oj»posito side a larger, somewhat crescentic, coucavo-couvex 



