152 Prof. II. G. Seeley. The Shoulder Girdle and [June 



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When the bones occur separate the scapula can usually be fit 

 to the coracoid ; then the surface which formed part of the articulation 

 for the humerus is clearly distinguishable from the surface which 

 joined the coracoid. And if the an tero- posterior extent, or measure- 

 ment from within outward, of the coracoid surface which articul 

 with the scapula is taken, it will be found to be greatly exceeded by t' 

 length of the opposed surface of the scapula, as it extends from the 

 humeral articulation forward to the clavicle. So that there is a f 

 edge of the scapula, which is cartilaginous, extending in front of 

 coracoid articulation, and between that articulation and the clavi 

 This surface is distinct from the coracoid surface, first in being mu 

 thinner; and, secondly, in commonly making an angle with that 

 surface, though I do not attach much importance to the latter cir- 

 cumstance, as it may be affected by conditions of preservation and 

 completeness of ossification. In one species of Ophthalmosaurus, in 

 the British Museum, a part of this margin of the scapula anterior to 

 the coracoid is concave and completely ossified where it formed part 

 of the coracoid foramen (fig. 1, lower right-hand figure), but anterior 

 to that is the unossified surface, which I suppose to have been for the 

 precoracoid cartilage. On the inner anterior margin of the coracoid 

 will also be found a surface, which indicates a cartilage, which I 

 believe met the clavicle. The examination of the skeleton shows that 

 the tripartite division of the scapula at its articular end, as figured 

 by Cuvier, and as represented by Sir E. Home, to whom the sternal 

 bones were first pointed out in detail by Buckland, as drawn by De la 

 Beche for Sir E. Home, as represented in Professor Huxley's figure 9 

 and as affirmed by myself, cannot be regarded as illusory or fallacious 

 on the evidence given ; and at present no reference has been made to 

 any skeleton from which such an inference could be drawn, or even in 

 which the different condition affirmed by Mr. Hulke could be seen, 

 though there is no reason why such a condition should not be found. 



The importance of this discussion centres round the significance of 

 the notch or concavity on the anterior border of the coracoid, which 

 is placed towards the scapular margin. Does that notch represent 

 the coracoid foramen of existing Reptiles? Such a foramen is seen in 

 the coracoid bone in Lizards and Hatteria, and has been regarded as 

 marking the union of the precoracoid and coracoid elements into one 

 bone, and on that account I have spoken of it as the precoracoid 

 foramen. It is more distinct in Amphibians, though it is differently 

 placed. It occurs in Crocodiles. Among extinct animals it is found 

 in the Saurischia and Ornithischia. It is present in the scapular arch 

 of Pareiasaurus and Anomodonts. It may be compared to the fora- 

 men in OrnitliorTiyncTius between the scapula and precoracoid. If the 

 notch in the coracoid of Ichthyosaurus, which is towards the scapula, 

 should be regarded as representing the coracoid foramen of any of 



