216 



— aiul Ihoso of B a i I s I' 1 1 m-c llic connective tissue fibres 

 as such. 



The fil)rill;e dcseriht-d l)y Lewis as eoiilaiiiini* mito- 

 chondria are the long delicate protoplasmic eonneclioiis 

 between the tissue cells, fibroblasts and epilhelial cells, 

 and they play quite another r(Me for the cells liian do Ihe 

 connective tissue fibrilUi' accordinj; to Raitsell; the latter 

 are the actual supporting apparatus of the tissue cells in vivo 

 and a product of the coagidable substances of the humors. 



According to M. R. Lewis she never observed the mito- 

 chondria to fuse into strands or become arranged in rows 

 to form connective tissue fibrills such as sevei'a! investiga- 

 tors have stated. 



The formation of intercellular substance of cartilage can 

 probably successfully be studied in \ilro. Carrel and 

 Burrows ^*) have cultivated conjugal cartilage. They 

 observed that the cartilage grew in the same culture and 

 increased very much in size. They did not observe any 

 disintegration of the hyaline substance in the way Fischer 

 19*) has described it, as being the case with the cartilage 

 from the eycbulb of the chicken. I never observed any for- 

 mation of hyaline substance in vitro. A slight variation 

 in the composition of the culture medium would probably 

 cause the cartilage cells to form intercellular substance; 

 it is, however, still an unknown field. It is quite remark- 

 able that the cartilage from the pars cartilago sclera? 

 of the chicken eye. disintegrates entirely when embedded 

 in the plasma medium and the cells die. but as soon as 

 it is placed on the free surface of the clot, il coinmenccs 

 to grow and the cells mullij)ly. This fact seems to indicate 

 that the physical forces prevailing on the surface of the 

 clot is a conditio sine ([ u a non for the growth of 

 the cartilage cells in vitro. 



(Concerning the investigation of the various bone-sub- 

 stances and the bone-forming elements in vilro very little 

 or nothing at all has been published so far. 



