THE OSSEOUS SYSTEM. 311 



the nose, joints, symphyses, and synchondroses ; a second disappears 

 altogether in the course of development (certain cranial cartilages, vide 



cells in the same sense, being merely the nuclei of Schwann and the nucleated form of the 

 corpuscles to which we have referred above. 



Whatever Schwann's words may indicate, then, his observations tend to precisely the 

 same conclusion as our own. 



Henle (" Allg. Anat," pp. 803-808) follows Schwann, and equally fails to discriminate the 

 cells in Pelobaies from the " cells" in the fostal pig. 



Reichert (in his admirable work, " Ueber das Bindegewebe," 1845) recognizes the fact that 

 the cartilage-corpuscles are " nuclei" in Schwann's sense, and refers the appearance of a 

 distinct wall in the cavities, to an optical delusion. He asserts that young cartilage is com- 

 posed of distinct cells closely united together, without any measurable intercellular sub- 

 stance ; as the cartilage grows, the latter increases, and eventually the cell-walls disappear. 

 The only evidence of the existence of these cells and intercellular substance offered by 

 Reichert, however, is the mode in which the tissue may be broken up ; a kind of evidence 

 whose value the purport of the rest of his book is to reduce (and most successfully) to 

 nothing. 



In effect, therefore, Reichert's observations come to the result already stated, that the 

 festal cartilage is composed of a homogeneous matrix, in which the corpuscles are dis- 

 persed. 



Robin (" Observations sur 1'Osteogenie") takes nearly the same view of the structure of 

 cartilage as that we have indicated. " Cartilage is composed," he says, " of a homogeneous, 

 amorphous, dense, elastic, hyaline basis (substance fondamentale], in which cavities are hollowed 

 out, cartilage-cavities. In each of these cavities we find one or many (sometimes 20 to 30) 

 cells, cartilage-cells^ whose parietes cannot be demonstrated to be distinct from their cavity. 



These cells are more or less granular, and have a nucleolated nucleus In the foetus, 



up to the age of four or five months, more or less, the cartilage cavities do not enclose one or 

 more cells, but one or many masses of yellowish granulations, all of nearly the same size. 

 These masses are more or less distinctly defined at their edges, in general indistinctly, and 

 nearly reproduce the form of the cavity without ever filling it. They may be called carti- 

 lage-corpuscles. Authors have not generally remarked this fact. By degrees the cells which 

 replace these corpuscles are developed. These cells are formed all at once ; but the grades 

 of the process as regards the commencing cell or the pre-existing granulations are as yet but 



little known Some authors wrongly call the cavities excavated in the fundamental 



substance, cartilage-cells ; and to the true cartilage-cells and masses of yellowish granulations 

 or corpuscles, referred to above as existing in the fostal state alone, they give the name of 

 contents.''' 1 



Remak ( :{ Ueber die Entstehung des Bindegewebes und des Knorpels," Muller's " Archiv," 

 1851-2) appears to have been the first, definitely to recognize the cartilage-corpuscles, as the 

 homologues of the primordial utricles of plants, a great step, and one which appears to us 

 to lead to most important consequences. Like Schwann, however, led away by the gene- 

 rally assumed anatomical independence of the vegetable cells, Remak interprets the struc- 

 ture of cartilage in the same manner, and speaks of the secretion of the chondrinous wall 

 by the primordial utricles, as " parietal-substance" within the primary cell-membranes. 

 He adduces no evidence, however, that the facts are other than as we have stated them 

 to be. 



Virchow (" Die Identitat von Knochen-, Knorpel-, und Bindegewebe-ktfrperchen so wie 

 uber Schleirngewebe," " Verhandlung d. Phys. Med. Gesellschaft," 1852) is an important wit- 

 ness in this matter. He says, " I have anew convinced myself that the so-called cartilage- 

 corpuscles are actual cells which lie in a cavity of the basis (Grundsubstanz}, or in a cell- 

 cavity presenting a double contour, and possess a membrane, granular contents, and a fre- 

 quently nucleolated nucleus. In the neighborhood of the line of ossification, in growing 

 cartilages, as well as in the young callus-cartilage of fractures, these cells are of very large 

 size, clear, and round ; in the neighborhood of the articular extremities, excessively small, 



