CARTILAGENEOUS TISSUE. 549 



the excess of this acid removed with sugar of lead, and the lead removed 

 from the filtrate by H^S. If further purification is necessary, the acid is 

 precipitated with alcohol, the precipitate dissolved in water, this solu- 

 tion dialyzed and precipitated again with alcohol this solution in water 

 and precipitation with alcohol being repeated a few times and lastly 

 the acid is treated with alcohol and ether. Other methods for the prepara- 

 tion of the acid (from the septum narium of the pig) have been suggested 

 by SCHMIEDEBERG and KONDO. 



The collagen of the cartilage gives, according to C. MORNER, a gelatin 

 which contains only 16.4 per cent N, and which can hardly be considered 

 identical with ordinary gelatin. 



In the above-mentioned cartilages of full-grown animals the chon- 

 droitin-sulphuric acid and chondromucoid, perhaps also the collagen, 

 are found surrounding the cells as round balls or lumps. These balls 

 (MORNER'S chondrin-balls) , which give a blue color with methyl-violet, 

 lie in the meshes of a trabecular structure, which is colored when 

 brought in contact with tropseolin. 



The albumoid is a nitrogenized body which contains loosely com- 

 bined sulphur. It is soluble with difficulty in acids and alkalies and 

 resembles keratin in many respects, but differs from it by being soluble 

 in gastric juice. In other respects it resembles elastin, but differs from 

 this substance in containing sulphur. This albumoid gives the color 

 reactions of the protein bodies. 



Cartilage gelatin and the albumoid may be prepared according to 

 the folowing method of MORNER: First remove the chondromucoid 

 and chondroitin-sulphuric acid by extraction with dilute caustic potash 

 (0.2-0.5 per cent), remove the alkali from the remaining cartilage by 

 water, and then boil with water in a PAPIN'S digester. The collagen 

 passes into solution as gelatin, while the albumoid remains undissolved 

 (contaminated by the cartilage-cells). The gelatin may be purified by 

 precipitating with sodium sulphate, which must be added to saturation 

 in the faintly acidified solution, redissolving the precipitate in water, 

 dialyzing well, and precipitating with alcohol. 



In MORNER'S experience no albumoid is found in young cartilage, 

 but only the three first-mentioned constituents. Nevertheless, the young 

 cartilage contains about the same amounts of nitrogen and mineral 

 substances as the old. The cartilage of the ray (Raja batis LIN.), which 

 has been investigated by LoNNBERG, 1 contains no albumoid and only 

 a little chondromucoid, but a large proportion of chondroitin-sulphuric 

 acid and collagen. 



According to PFLUGER and HANDEL, 2 glycogen occurs to a slight 



1 Maly's Jahresber., 19, 325. 



2 Pfliiger in Pfliiger's Arch., 92; Handel, ibid. 



