102 PROFESSOR OWEN ON THE OSTEOLOGY OF 



metapophysis begins to project from the anterior angle of the diapophysis in the 

 seventh vertebra, progressively increases in size in succeeding vertebrae, and rises in 

 position close to the upper zygapophysis in the last dorsal. In the adult male skeleton 

 in the College of Surgeons, the metapophysis appears as a tubercle, near the base of 

 the upper zygapophysis of the twelfth dorsal : it is equally distinct on the first lumbar, 

 but subsides to a slight eminence on the succeeding lumbar vertebrae. The anapophysis 

 is only distinguishable from the diapophysis upon the first lumbar vertebra, where it 

 serves to illustrate the true relation of the diapophysis of that vertebra to those of the 

 antecedent dorsals and the succeeding lumbars. 



In comparing the last dorsal vertebra with that of Man, one may notice the smaller 

 size of the body and the shorter neural spine of the Orang ; and that the neural arch of 

 the Orang is entire below, not notched. 



In the Negro and Australian skeletons the body of the first dorsal vertebra (PI. XXXIV. 

 fig. 2, 1 ) is relatively larger than in the Chimpanzee, particularly anteriorly : it is less 

 convex below ; it is larger in proportion to the neural arch and its appendages than in 

 the Gorilla. The transverse processes are thicker and are more inclined backwards and 

 upwards : the spinous process is thicker and relatively much shorter, and more inclined 

 downwards. 



In the second dorsal vertebra (i&. 2) the centrum is increased in vertical and antero- 

 posterior extent: the upper zygapophyses are nearer to each other and are more pro-- 

 duced than in the first dorsal, whereby the upper notch of the neural arch becomes 

 deeper and narrower. The diapophyses are longer and thinner. The neural spine is 

 also thinner, and the lower zygapophyses are smaller. This vertebra differs from its 

 homologue in the Gorilla and Chimpanzee in the more backward direction of tbe diapo- 

 physes and the more outward aspect of their articular surface. The upper emargination 

 of the neural arch is less deep : the neural spine is absolutely shorter and smaller. The 

 body IS relatively larger than in the Gorilla, and is absolutely larger than in the Chim- 

 panzee, and the pedicles of the neural arch are longer in conformity with the wider 

 neural canal. 



The third dorsal vertebra (ib. 3 ) differs from the second in a slight diminution in the 

 transverse and increase in the antero-posterior extent of the centrum : the diapophysis 

 and neural spine are somewhat thicker : the upper neural emargination is narrower. It 

 differs from that of tbe Gorilla and Chimpanzee in the minor length of the neural spine, 

 the greater relative breadth of the centrum, the greater length of the pedicles and con- 

 comitant expanse of the neural canal. The accessory tubercle is less distinctly developed 

 upon the diapophysis than it is in the Chimpanzee. 



In the fourth dorsal vertebra {ib. 4 ) the same general differences, in comparison with 

 the Gorilla and Chimpanzee, are repeated, with a greater development of the diapophysis 

 backwards and an increased size of the accessory tubercle. 



In the seventh dorsal vertebra {ib. 7 ) the progressive increase in the size of the cen- 



