of the Pelecanus Aquilus of Linnceus. 7 



termediate cartilages. Of these the vertebral portion is tl , 

 largest and strongest, and forms in the lower ribs about one half 

 of the whole. The sternum, clavicles, and particularly the 

 bones of the upper extremities, are of a size and strength out of 

 all proportion with the other parts of the skeleton. The pecto- 

 ral process of the sternum is very deep, to assist as much as pos- 

 sible in giving an adequate surface of attachment to the pectoral 

 muscles. The relative proportions of the bones of the anterior 

 and posterior extremities are so extraordinary as to merit parti- 

 cular observation ; on which account I shall mention some of 

 them. 



The length of the Os humeri is ... 7^ inches. 



2 



~4 



hat of the os humeri as 



Finn . . . 

 Radius 

 Os femoris 

 Tibia . . . 



The length of the os femoris then is to 



one to three and five-eighths ; and to that of the ulna or radius 



as one to four and three-fourths. 



The proportions of weight are yet more extraordinary. 



The weight of the Os humeri is . . . 175 grains. 



Ulna 140 ' 



Radius . ► . . - 64 

 Os femoris . . » . 11 



Tibia 22 



The weight of the os femoris is to that of the os humeri as about 

 one to fourteen ; and to that of the ulna as about one to eleven. 



The bones of the pelvis are so light as to be in many parts 

 transparent ; and further to obviate the effect of weight, there is 

 a double row of foramina running down each side of the os sa- 

 crum,, which in the fresh state are filled with a thin ligament, to 



which 



