112 THE CONNECTIVE TISSUES, BY A. ROLLETT. 



that the young cartilage cells are provided with two membranes, 

 of which the innermost corresponds to the primordial utricle of 

 the vegetable cell. In the act of cell division this last alone 

 participates. The proper substance of the cartilage is depo- 

 sited either between the external and internal membranes, or 

 between the former and the daughter cells, and indeed, in the 

 first instance, on the inner surface of the external membrane ; 

 and in this mode the vesicular cavities in the cartilage arise. 

 Each newly developed daughter cell immediately forms again an 

 external membrane, upon the inner surface of which fresh car- 

 tilage is deposited, whilst the cells again subdivide ; and there 

 is thus developed a nest of cartilage cells contained one within 

 another. By the fusion of the several cartilaginous laminae 

 with one another, and the disappearance of the cell mem- 

 branes which served as a framework for its deposit, the matrix 

 of the cartilage is produced, which thus appears to be an 

 intercellular formation, and may be called " parietal substance." 

 It is easy to perceive that the views of Remak were con- 

 structed on the cell theory of his day. 



If, however, we abstract the two hypothetically present mem- 

 branes of Remak, the formation of chondrin-yielding substance, 

 described by him, and its relation to the cells, corresponds 

 exactly to the processes observed in the development of carti- 

 lage, and to the appearances which may be obtained by break- 

 ing up mature cartilage. Fiirstenberg, who was the first to 

 accomplish this, regarded the layers of chondrin-yielding 

 substance as thickened cell membrane, and showed that in 

 certain cartilages the whole matrix was to be considered as 

 composed of such thickened membranes belonging to succes- 

 sive generations of mother and daughter cells. Kb'lliker* also 

 maintains the capsules of cartilage to be cell membranes, and to 

 represent the secondary membrane of the vegetable cell. In 

 some few cartilages the matrix is composed of these alone, 

 but in others again, especially in those in which the division 

 into cell territories is not completely effected, a large and often 

 the chief part of the matrix is formed of pure intercellular 

 substance lying between the cell membranes. Kolliker's view is 



* Gewebelehre, 1867, p. 64. 



