132 THE CONNECTIVE TISSUES, BY A ROLLETT. 



are absent, the cells appear to be in direct contact with one 

 another. Even then, however, when the cells have become 

 somewhat shrivelled, a very delicate structure may be distin- 

 guished, formed by the presence of small quantities of the 

 matrix intervening between each of the vertical rows. The 

 septa intermediate to the cells in the latter case are arranged like 

 the steps of a ladder (see the illustration) between the adjoin- 

 ing longitudinal trabeculse. Still more internal to the region of 

 large cells, the thicker vertical trabeculse become the seat of the 

 deposit of the lime salts, in the form of small granules or con- 

 fused masses on their internal surface, and at the same time 

 they become somewhat thicker. We then reach the region of 

 calcified cartilage, which, according to H. Miiller,* usually pre- 

 cedes the true process of ossification. A very beautiful mode of 

 supplementing the images hitherto only seen in longitudinal 

 section, and which have been best described byWaldeyer,~f*is that 

 by which transverse sections are examined that are successively 

 carried through the several regions above described. 



The appearances presented by transverse sections of the 

 calcified cartilage are especially worthy of notice. In these, 

 calcified rings surrounding one or several of the large cells, 

 and characterised by their granular or cloudy appearance, come 

 very distinctly into view. If the transverse section approxi- 

 mates nearer to the bone, the calcified rings increase in thick- 

 ness, and still lower down the cells which occupy the calcified 

 rings become smaller, more numerous (fig. 13), and more strongly 

 granular. Beneath these cells we find masses of protoplasm 

 often of considerable size, containing two or more nuclei, 

 together with a great number of small nuclei. The many- 

 nucleated cells have been rightly associated by GegenbaurJ 

 and Waldeyer with the myeloplaxes described by Robin. |j 

 The selection of successively lower planes for the transverse 

 section thus leads from the large-celled region, the calcified 



* Loc. cit., p. 157. 



t Loc. cit., p. 359, v. Taf. 22, fig. 2. 



| Loc. cit., p. 349. 



Loc. cit., p. 362. 



'[ Journal do la Anatomic, de la Physiologic, Tom. i., p. 



