156 Prof. H. G. Seeley. The Shoulder Girdle and [June 



In fig. 4 it approaches nearer to the form of a foramen perhaps tl 

 in any other specimen, and in the interspace between the truncat 

 anterior margin of the coracoid and the clavicle a surface is left 

 smooth and distinct from the matrix in Laurillard's drawing, which 

 may be only a hole in the matrix,* but that appearance possibly may 

 be the foundation for the supposed epicoracoid described by the late 

 Sir R. Owen in 1839 and 1866. 



I fail to find any support for the critical position taken by Mr. 

 Hulke, or for his restoration of the shoulder girdle of Ichthyosaurus 

 (' Geol. Soc. Quart. Jour.,' 1883, p. 45), in the criticism which he 

 makes of the authors referred to, who all take the view of anterior 

 extension of the scapula in advance of the coracoid articulation; 



cor 



FlGL 5. Mr. Hulke's restoration of the I chthyo saurian shoulder girdle, ic, inter- 

 clavicle ; cl, clavicle; so, scapula; cor, coracoid; gl, articulation for 

 humerus. 



while in Mr. Hulke's figure the breadth of the articular end of the 

 scapula is made the same as the breadth of the surface of the coracoid 

 with which it unites. This is at variance with every specimen known 

 to me. The difference between Mr. Hulke, on the one hand, and other 

 writers is not a matter of opinion or interpretation, but of fact, which 

 can only be demonstrated by examination of specimens, or figures in 

 detail of the structure, shown in all specimens which 1 have seen in 

 skeletons well preserved. 



I have stated that this identification of the precoracoid accounts for 

 the structure of the shoulder girdle, and explains its homology. As 

 both clauses of this statement are challenged, I may state, further, that 

 by " structure " I mean the mode of arrangement of the bones by which 

 the cartilaginous surface of the scapula extends forward in advance of 



* Professor Albert Gaudry has had the kindness to examine this specimen for \ 

 me, and has had the matrix partly removed so as to make the relations of the 

 scapula and coracoid more evident. He finds no trace either of ossification or 

 cartilage between the coracoid and clavicle. 



