164 MR. TOYNBEE ON THE ORGANIZATION AND NUTRITION 



Its extremities were smooth, and appeared to be covered by a synovial membrane, 

 but the cells here did not present any difference from those of the shaft. 



In no portion of either shaft or extremities could any vessels or canals be observed. 



b. In a foetal Calf, which measured fifteen lines between the points above indicated, 

 the rudimentary os femoris was a line and a quarter in length, and one fourth of a 

 line in breadth in its middle part ; the extremities were somewhat expanded. 



Excepting a small osseous ring at its median part, this rudimentary os femoris was 

 entirely cartilaginous, and its cartilage was composed of large rounded cells, loosely 

 connected together by a gelatinous substance. The cells of the articular margin dif- 

 fered from those in the Calf of twelve lines in length, described in the preceding dis- 

 section, in being elongated, and in having their long axis parallel with the free sur- 

 face of the cartilage. The synovial surface of these cells presented a defined border, 

 beyond which were flattened scales, each having an elongated process. There was 

 no appearance of canals or vessels in any part of this cartilage. 



c. In a foetal Calf, measuring seventeen lines from the vertex of the head to the 

 commencement of the caudal vertebrae, the cartilage of the inferior femoral epiphysis 

 presented no appearance of canals. Its cells were large and round, and their con- 

 necting medium lax and easily compressible. On compressing a thick section of the 

 extremity of the cartilaginous femur, the flattened cells of the epithelium of its syno- 

 vial membrane were distinctly seen ; they were as large as those of the epithelium of 

 the mouth in the adult human subject ; one of their surfaces faced the articular car- 

 tilage, the other the cavity of the joint. 



d. In a foetal Calf, measuring 2J inches between the points above alluded to, the 

 OS humeri, which was two lines and a half in length, was ossified to the extent of three 

 fourths of a line at its central position. Its articular surfaces were smooth and de- 

 fined, and it presented no appearance of canals. The cells towards the articular sur- 

 face, as in the preceding dissections, were elongated and flat. 



e. In a foetal Calf, measuring three inches in length, the epiphysal extremities of 

 the cartilaginous femur presented no canals, and the arrangement of the cells of the 

 cartilage was the same as in the above dissections. 



The foetal Calves in all the above dissections had been injected, and in each case 

 the extremities of the cartilaginous rudimentary bone were found to be surrounded 

 by large ramifications of sanguiferous vessels. 



The above observations on the nutrition of articular cartilage during the earliest 

 periods of its development have been principally confined to preparations of foetal 

 Calves, from my not having been able to procure those of the human foetus suffi- 

 ciently numerous and varied for my purpose. My more limited examinations, how- 

 ever, of the human foetus, have led me also to the conclusions, that during the most 

 early periods, the cartilage of the epiphysal extremities of bones does not contain any 

 blood-vessels, and that notwithstanding their absence, the cells of this cartilage are 

 developed, and its growth carried on ; and that at the same time the cells of the epi- 



