ON THE STRUCTURE OF HYALINE CARTILAGE. 19 



considered as proved except their existence in cartilage, but 

 analogy with other tissues suggests that they are applied to 

 the surface of the cylindrical bodies seen in silver and serum 

 preparations (primary bundles of the author as previously 

 described in regard to other connective tissues). 



In reference to the appearance of a coherent circular mass 

 bulging from the end of a separated portion of such a band 

 or cylinder the following explanation is suggested : — It is 

 highly probable, fof reasons which need not now be entered 

 on, that in all the forms of connective tissue these bands or 

 primary bundles are invested by a resistant delicate mem- 

 brane on Avhich the narrow elongated cells lie. In all tissues 

 in which the author has seen them these bulgings have been 

 occasionally observed, and have been invariably snared at the 

 point of their escape from the cylinder by a sharply defined 

 ring continuous with the contour of the cylinder. These 

 appearances may be well studied in the cornea of a frog which 

 has been broken down by acute inflammation, however 

 produced, which has lasted about a week, the cornea being 

 then stained in gold. 



The production of giant cells from healthy cartilage by 

 simple prolonged maceration in aqueous humour in a sealed 

 preparation must be considered, in the present state of patho- 

 logical inquiry, as a fact of great importance. During the 

 author's experiments with caustic potash, especially in cartilage, 

 he had frequently seen irregular masses occurring in imper- 

 fectly successful experiments which resembled in contour, size, 

 and the arrangement of nuclear vacuoles the bodies known as 

 giant cells, whilst at the same time they could be recognised 

 as partially disintegrated single and double layers of epithelial 

 cells and intermediate substance. So accurate was this re- 

 semblance that the hypothesis which the author believes to 

 have received complete confirmation from the aqueous- 

 humour preparation had already presented itself to his mind. 

 If giant cells can be isolated from healthy adult cartilage 

 by simple maceration, it is unnecessary to assign any other 

 reason for their presence in the neighbourhood of cartilage 

 and bone which are undergoing absorption during the process 

 of ossification than that, during the disintegration of the 

 absorbed structure, sheets and fragments of sheets of flat 

 (epithelial) cells are set free, but before they are loosened 

 from their connection they have become so much disintegrated 

 that the lines of junction of the individual cells have become 

 obliterated, and nothing remains but a shapeless protoplasmic 

 mass, containing either nuclei still entire or vacuoles cor- 

 responding to nuclei that have undergone destruction. The 



