Thecodontosaunis and Palffiosuurus. 



1.07 



No. i)7 is Jill instructive tVagment ((i^^ 7), sliowiii/j; the 

 articular eiul of the scapula in an uncompressed condition. 



Kunipral articulnr 

 surf'iice. 



Scapula of Palceosaurns. Jurist. Mas. no. U7. 4- nat. size. 



The principal specimen, no. 80, is exposed on tiie internal 

 aspect, and consequently shows no indication of the articular 

 surface and only a slight film of the coracoid and a ])ortion of 

 the impression from which the bone is lost. The scapula is 

 concave in length on the posterior surface, with a sharp ante- 

 rior border, which was reflected outward in the region in 

 which the thickening of the anterior crest of the scapula is 

 usucilly found. The bone does not appear to have been more 

 than 0^ inches long ; it is 1^ incii wide towards the free end, 

 1 inch wide in the middle, 2y^ inches wide towards the 

 iiumeral articulation ; but it is fractured in front, and probably 

 had a width of 3^ inches. The coracoid is very imperfectly 

 indicated in this and the other specimens in which it appears 

 to be ])artially preserved. The substance of the coracoid is 

 YQ inch thick, which is only half the thickness of the fractured 

 anterior margin of the scapula. There is some indication that 

 the surfaces of scaj)ula and coracoid, which contributed to 

 make the articulation for the humerus, met each other at an 

 angle. Both these surfaces exceed an inch in length. There 

 is a slight eminence on the surface on the cast in the region 

 of the coracoid, which may indicate a foramen. It seems 

 ])robable that the scapuhe here referred to belong to different 

 species ; and it might be anticipated that Palivoaaurus will 

 liave a comparatively large and strong articulation in the 

 shoulder-girdle when comj)ared with Thecodontoscwrus. It is 

 possible that the bone no. 90 may pertain to the 1 itter genus 



