basis having been afterwards dried : this basis consists of the proximate 

 organic principles called ' glutin ' and ' chondrin.' Hunterian. 



7. The shaft of the Human humerus, from which the animal or gelatinous matter 

 has been driven off by heat, and the incombustible earthy hardening salts left 

 behind. Presented by Edward Stanley, Esq., F.R.S. 



The following gives the average result of the chemical analyses of Human bone : 



Phosphate of lime, with a trace of fluate of lime 59'63 



Carbonate of lime 7'33 



Phosphate of magnesia 1-32 



Sulphate, carbonate and chlorate of soda 0'69 



Glutin and chondrin 2970 



Oil . 1-33 



100-00 



THE VERTEBRA, OR PRIMARY SEGMENT OF THE ENDO-SKELETON. 



A. Permanent or arrested conditions illustrative of stages of development of 

 the vertebra. 



8. A Lancelot (Branchiostoma lubricum, Costa ; Amphioxus lanceolatus, Yarrell), with 



the integuments and muscles of the right side removed, together with the 

 viscera, exposing the continuous cylindrical gelatinous chord (' chorda dorsalis,' 

 or notochord) : this, with its fibro-membranous sheath, represents the bodies or 

 central elements of the vertebrae, and the aponeurotic processes, sheathing the 

 neural axis and forming intermuscular septa, represent the peripheral elements 

 of the vertebrae. Prepared by Mr. George Hansbrow, Anatomical Student. 



9. A transverse section of the caudal portion of the vertebral column of a Lamprey 



(Petromyzon marinus), showing the persistent notochord and its double aponeu- 

 rotic sheath, with two of the pairs of cartilaginous laminae developed upon the 

 aponeurotic wall of the upper (neural) canal, representing the ' neurapophyses' of 

 ossified vertebras ; and with two of the pairs of cartilaginous laminae developed 

 from the aponeurotic wall of the lower (haemal) canal, representing the ' haem- 

 apophyses ' of ossified vertebrae. 



Prepared by Mr. George Hansbrow, Anatomical Student. 



