574 THE MICROSCOPE. 



Professor Quekett has given, in the Microscopical Society 's 

 Transactions, an excellent ac- 

 count of the " Intimate Struc- 

 ture of Bone." To this paper 

 we are indebted for the fol- 

 lowing microscopic investiga- 

 tion of bone: 



"Bone consists of a hard 

 and soft part; the hard is 

 composed of carbonate, phos- 

 phate, and fluate of lime, and 

 of carbonate and phosphate of 

 magnesia, deposited in a carti- 

 laginous or other matrix; whilst 

 the soft consists of that matrix, 

 and of the periosteum which 

 invests the outer surface of 

 Fig. 316. The same, viewed under a the bone, and of the medullary 



lower power, appear to be a series of mem b rane which Hues its 

 small black dots. 



interior or medullary cavity, 

 and is continued into the 

 minutest pores. If we take 

 for examination a long bone 

 of one of the extremities of 

 the human subject, or of any 

 mammalian animal, we shall 

 find that it consists of a body 

 or shaft and two extremities ; if 

 a vertical section of such a bone 

 be made, we shall also find that 

 the middle of the shaft contains 

 a central cavity, termed the 

 medullary cavity, which ex- 

 tends as a canal throughout the 

 whole of it, or else is entirely 



J?ig 317. -A transverse section of the partially filled Up With a 



Humerus, or fore-arm bone, of a r J 



Turtle (Cheionia mi/das), it ex- cellular bony structure, whicn 



hibits traces of Haversian canals, ,, fprmpfl Pinpplli and 



with a slight tendency to a con- cells are teimea cane an, ana 



centric arrangement of bone-cells fa Q structure a Cancellated 

 around them. The bone-cells are ^\ c i 



large and very numerous, but structure. On a more careim 



row.* f r the m st Part in paraUel examination of the bony sub- 



