RICKETTY CARTILAGE. 479 



The enlargement and multiplication of the individual 

 cells takes place in the same manner, as in the cases we 

 have already considered ; but inasmuch as at a later 

 period individual parts in the cartilages, that properly 

 ought to have become bone, do not calcify, and especially 

 a formation of medullary spaces often takes place a long 

 way up above the border of calcification in many of 

 these rhachitic parts the whole history of the develop- 

 ment of bone is clearly revealed in a connected form. 

 Large and often very vascular conical processes of 

 fibrous medullary tissue are seen extending upwards from 

 the bone into the cartilage, and it may be very distinctly 

 perceived, that these processes do not force their way 

 into the cartilage from without, but that they owe their 

 origin to a fibrillation of the intercellular substance of the 

 cartilage itself. It is around them chiefly that the osteoid 

 transformation of cartilage also can best be seen, and 

 particularly that the gradual conversion of a cartilage- 

 corpuscle into a bone-corpuscle can very distinctly be 

 witnessed. Out of the cartilage-corpuscle which has a 

 moderately thick capsular membrane, arises a structure, 

 provided with a capsule continually increasing in thick- 

 ness, within which the space for the cell constantly 

 grows smaller, and which, when it has attained a certain 

 degree of thickness, acquires indentations on its inner wall, 

 like the so-called dotted canals of vegetable cells. Such 

 is the mode in which the first rudiments of the bone-cor- 

 puscle are traced, after which a fusion of the capsule with 

 the basis-substance very generally ensues, and with the 

 production of anastomosing processes from the cells the 

 formation of the bone-corpuscle is completed. At times 

 isolated osteoid cartilage-corpuscles calcify alone without 

 the occurrence of any fusion ; and whilst between them 

 lies the ordinary intercellular substance of cartilage, the 

 capsules of the osteoid corpuscles fill themselves com- 



