THE CONNECTIVE SUBSTANCE GROUP. 85 



from the frog ; strip it of pericliondrium and mount in serum. 

 The shoulder-girdle of the triton (newt) may also be employed. 

 It will then be seen that there are numbers of granular cor- 

 puscles, with nuclei scattered irregularly throughout an ap- 

 parently homogeneous, i.e., structureless matrix. If now a 

 little water be added to the preparation, it will be seen that the 

 corpuscles are made to shrivel, and in so doing they expose 

 the wall of the cavity or capsule in which they lie. The cor- 

 puscles do not appear to have any uniform size or shape : some- 

 times they are single ; again they are double (daughter-cells) ; 

 occasionally they are united with the corpuscles in adjacent 

 capsules. The nucleus is apt to be round and full ; the corpus- 

 cles are apt to be filled with dark spherical bodies which are 

 usually fatty molecules, as may be shown by employing a di- 

 lute solution of osmic acid (I per cent.). 



Using the silver method it will be seen that there exists, in the apparently 

 homogeneous matrix, numbers of corpuscles whose nature is not fully under- 

 stood. Incidentally it may be mentioned that the silver method often exhibits 

 curious markings in all tissues. 



Sometimes these appearances are due to the silver itself, and some caution 

 is therefore necessary in deducing conclusions from the method. 



The gold method l shows that there are concentric rings about the capsules, 

 but it is highly probable that this phenomenon is artificial. 



Ranvier recommends, as a staining fluid, purpurine, the 

 formula of which is as follows : Take one gramme of powdered 

 alum and add to it two hundred grammes of distilled water, 

 which boil in a porcelain dish. To this solution add some pow- 

 dered purpurine diluted with water. If the boiling be now con- 

 tinued, a portion of the purpurine will dissolve. Filter while 

 warm, and receive the colored fluid in a flask which contains 

 60 c.c. of alcohol. This liquid has a rose-orange color. The 

 nuclei of the corpuscles will be colored red and have a double 

 contour ; the cell-body will be bright red. 



Hyaline cartilage may be well exhibited in the respiratory 

 tract of young children, as in the cricoid cartilage of an infant 

 two or three years old. 



Yellow elastic or reticular cartilage is a very distinctive 

 form. It consists of the hyaline variety permeated with elas- 

 tic networks. Examples of it may be obtained from the human 



1 See chapter on General Methods. 



