222 Royal Society : — 



Nevertheless I venture to affirm that 51' is the right scapula aud 

 not the left ; for it will not be denied that the anterior or glenoidal 

 end of the bone, as it now lies, is directed forwards, its posterior or 

 vertebral end backwards, and its glenoidal articular surface outwards 

 and forwards : it would be quite impossible to put a left scapula of 

 similar construction into this position. 



Further, the glenoidal end of this scapula remains in connexion 

 with what is obviously the glenoidal (or humeral) end of the right 

 coracoid (marked c in plate i.)- The author of the memoir, indeed, 

 gives a different interpretation of the osseous projection thus marked 

 il. c. p. 37) :— 



"The prominence beyond the left scapula (Plate I. 51') sug- 

 gested at first view the humeral end of the coracoid, but I believe it 

 to be part of the humerus corresponding with the tuberosity on the 

 ulnar side of the sessile semioval head, overarching the pneumatic 

 foramen in the bird." 



And this view is pictorially embodied in the restoration of the 

 humerus oi ArchcBopteryx given in plate ii. fig. 1. 



But a most distinct line of matrix separates the humerus from the 

 prominence in question, in which may be seen, with great clearness, 

 the glenoidal facet of the coracoid, as well as the excavation of the 

 exterior surface of the bone which is characteristic of the glenoidal, 

 or humeral, end of the coracoid in birds and pterodactyles. 



I think, then, there can be no question that the parts marked 51' 

 and c in Plate I. of the memoir cited are the right scapula and the 

 glenoidal end of the right coracoid, and not, as the author affirms, 

 the left scapula and a tuberosity of the humerus. 



5. Even apart from the fact that the humerus marked 53' lies in 

 almost undisturbed relation with the right pectoral arch, it is ob- 

 viously a right humerus. On no other supposition can the relative 

 position of the deltoid ridge and of the various contours of the bone 

 be accounted for. Nevertheless this is called " proximal half of left 

 humerus (53'), entire, and part of the distal half" at p. 34 of the 

 memoir cited. 



It is probably needless to pursue this part of the inquiry any 

 further. As the so-called right leg turns out to be the left, the so- 

 called left OS innominatum the right, and the so-called left scapula 

 and wing-bones to be those of the opposite side of the body, the 

 necessity of a corresponding rectification for the other limb-bones 

 needs no evidence. 



6. As both the hind limbs and one-half of the pelvis have just 

 such positions as they would readily assume if the hinder part of 

 the animal's body lay upon its ventral face, it is highly improbable 

 (to say the least) that the caudal and posterior trunk-vertebrae should 

 have turned round so as to present their ventral aspect to the eye, as 

 they do according to the memoir {I. c. p. 44). 



But I apprehend that evidence can be found in the vertebrae them- 

 selves sufficient to prove that their dorsal and not their ventral faces 

 are turned towards the eye. In several of the best-preserved of these 

 vertebriie, in fact, (and plate i. imperfectly shows this,) the remains 



