CONNECTIVE TISSUE. 



213 



vessels, medullary tissue, consisting of globular or spindle-shaped 

 corpuscles, with a slight amount of a myxomatous and fibrous 

 reticular basis-substance. Lower powers of the microscope reveal 

 that the boundary line between medullary and cartilage tissue in 

 some places is sharply defined, while in other places it is indistinct 

 or invisible. In the most peripheral portions of the medullary 

 tissue, i. e.j nearest the cartilage, we see rows of spindle-shaped 

 or oblong bodies, bear- 

 ing a close resemblance 

 to the medullary cor- 

 puscles found on the 

 boundaries of forming 

 bone-tissue. (See Fig. 

 84.) 



In the cartilage of 

 the knee-joint, at the 

 extremity of the femur 

 of new-born pups, we 

 meet not infrequently, 

 at the borders of a 

 medullary space, close 

 to the fully formed car- 

 tilage, with groups of 

 medullary corpuscles, 

 the peripheral portions 

 of which are beginning 

 to be infiltrated with 

 an apparently homoge- 

 neous basis-substance, 

 while the central por- 

 tion retains the charac- ^IG. 84< HYALINE CARTILAGE OF THE CONDYLE 



^-p 4-1,^ 4--\ OF TIBIA OF A HUMAN EMBRYO, FOUR MONTHS 



ter of the cartilage cor- OJD SAGITTAL SECTION . CHROMIC ACID 



puscle. Under these SPECIMEN. [PUBLISHED IN 1873.] 

 conditions, homoffene- 



7 . & . M, medullary canal, transversely cut, containing blood- 



OUS (in the Optical dl- vessels and medullary tissue; C, cartilage, with marked 

 ameter Semicircular) ter " tories in tne basis-substance. Magnified 200 diam- 



fields are projected into 



the caliber of the medullary space. Or a gradual transition of 

 medullary into cartilage tissue takes place at the border of the 

 medullary space, with the result that a number of spindle-shaped 

 medullary corpuscles are transformed into a territory of cartilage 

 tissue, which in this situation sometimes exhibits a delicate 





