838 ^fr. C. W. Andrews on the Development of 



The anterior ventral ramus is the largest and most im- 

 portant part of the scapula; its anterior border, a continuation 

 of that of the dorsal ramus, is at first rounded and concave as 

 far as the ])rominent tubercle above mentioned, then compa- 

 ratively sharp and thin, running inwards and forwards till, by 

 a sharp curve, it passes into the median border, with which it 

 makes an angle of about 45°. Tiie hinder border, forming the 

 anterior as well as part of the inner edge of the coraco-scapular 

 foramen, increases in thickness from without inwards and 

 then backwards to the junction with the anterior prolongation 

 with the coracoid, the surface for union with wliich is nearly 

 semicircular and is at riglit angles to the scapular symphysis. 

 This latter (fig. 2B), wliich occupies the inner end of the 

 thick posterior portion of the venti'al ramus, forms a nearly 

 rectangular surface, measuring 7 or 8 centim. long by 

 5 centim. deep ; its anterior dorsal angle is rounded, while 

 its anterior ventral angle is prolonged forward as the inner 

 edge of the thin anterior portion of the ventral ramus. The 

 symphysial surface is deeply pitted and channelled by blood- 

 vessels which passed into the thorax by a foramen between 

 the two scapulae at about the middle of the symphysis. 



The outer surface of the ventral ramus of the scapula is 

 nearly flat, but the visceral surface is divided into two areas — 

 a high posterior portion, where the bone is very thick and 

 convex antero- posteriorly, and a thin, depressed, slightly 

 concave anterior area, which is triangular in form and is 

 separated from the posterior portion by a step which runs 

 directly outwards from the upper anterior angle of the sym- 

 physis. This anterior region of the scapula does not meet 

 the corresponding portion of the opposite side in the oldest 

 specimen I have been able to examine, but is separated from 

 it by a narrow V-shaped interval. Probably the two sides 

 were united by cartilage, and in very old individuals ossifica- 

 tion may have extended inwards till they met in the middle 

 line. 



The above description is founded on a left scapula (R. 1966), 

 which, with an associated complete clavicle, is preserved in 

 the Leeds collection at the British Museum. Recently, on 

 examining Mr. Leeds's private collection, I noticed a shoulder- 

 girdle wanting the left scapula and clavicle, but found asso- 

 ciated with numerous vertebrge and the greater part of the 

 pelvis. Comparison of the two scapulae >shows that they are 

 exactly similar both in size and in details of structure, even 

 to the vascular impressions on the symphysial surface, so that 

 there can be no doubt that they belong to one and the same 

 individual. Tiie vertebrse and other bones present the 



