294 SPECIAL HISTOLOGY. 



towards the true bone by a sinuous contour, in which the limits, as it 

 were, of the individual lacunae are distinguishable, is not found either 

 exclusively in bones not yet fully formed, as Gerlach believes, nor only 

 at a more advanced age (from 30 upwards, and particularly in old men), 

 as H. Meyer states, but, at all events as far as my observation extends, 

 at all ages, from the complete development of the bone upwards, inva- 

 riably in every articulation, except that of the lower jaw and those on 

 the os hyoides.* 



The articular cartilage on the head of the femur, in a man 25 years 

 old, measured 1-1 J of a line in thickness ; on the condyles in the middle 

 1J, on the margin, j-1 line ; in ihefovea patellce, IJ-lf of a line ; in the 

 middle of the condyles of the tibia, 1J of a line ; at the borders, -J-fths 

 of a line; in the middle of the patella, IJ-ljths of a line ; in the glenoid 

 cavity of the tibia, J-f ths of a line, on the body of the astragalus, on 

 the upper side, fths, on the under, J, on its head, f ths of a line ; at the 

 base of the first metatarsal bone, - J, on its head Jd of a line, on 

 the inner cuneiform bone, in front, J J, behind, J fths of a line. In 

 the foetus, about the middle period of uterine life, the vessels of the 

 synovial membrane, according to Toynbee ("Phil. Transact.," 1841), 

 extend much further upon the articular cartilage ; of which fact, how- 

 ever, I have been unable to satisfy myself in the humerus of a five or 

 six month foetus, or in new-born infants. In pathological states endo- 

 genous cell-formation is met with in an unusual degree of perfection, and 

 more especially in all kinds of articular cartilages ; in which the parent 

 cells, frequently of very considerable size, with one or two generations 

 of secondary cells, and also containing fat, lie tolerably free in the fibrous 

 matrix, and admit of being readily isolated (vide also Ecker in Rosera 

 and Wunderlich's "Archiv," vol. II., 1843, p. 345). In the adult, the 

 articular cartilages are non-vascular, although the vessels of the syno- 

 vial membrane, at their border, often advance to some distance over them. 

 What Liston ("Med. Chir. Transact.," 1840, pp. 93-4) describes as 

 " vessels in the articular cartilage of several diseased joints, and as' run- 

 ning straight in parallel lines from the injected membrane of the bone 

 into the cartilage, and as joining at their further extremities in that 

 tissue, thus forming long loops," were certainly nothing more than the 

 normal vessels of cartilage, which (vide infra) may be very beautifully 

 displayed even in individuals 18 years old. There cannot, therefore, be 

 any question of inflammation of the cartilages in the adult, though they 

 doubtless suffer in morbid conditions of the bones upon which they rest, 

 or in inflammation of the synovial membrane. They frequently assume 

 a fibrous structure, a change which is often attended with a simultaneous 



* [This peculiarity of the bone beneath the articular cartilages was first pointed out by 

 Dr. Sharpey (Quain and Sharpey, 5th ed., p. clviii.), and is particularly described by Tomes 

 and De Morgan, 1. c., pp. 10, 11. TRS ] 



