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stance expands, and embraces a greater quantity of elements 

 of the connective tissue. It is difficult, at first sight, to 

 believe that an injected liquid forms a circumscribed mass in 

 the cellular tissue, if it be constituted simply of fibres. But 

 if it be believed that these fibres are very soft, and are easily 

 separated, it will be seen that the liquid, Avhilst rushing in, 

 forces back these fibres, and that then, being collected to- 

 gether great numbers, they form by their reunion a membrane, 

 more or less complete, which holds back the liquid, and pre- 

 vents it from spreading further. 



In order to obtain the dispersion, it suffices to displace 

 the fibres by rubbing the skin with which they are con- 

 tinuous. 



The injections of gelatine have the advantage of becoming 

 solid so soon as the animal is cold. One can then make 

 sections which show the diff'erent parts of the connective 

 tissue spread out by this noAV means of dissociation. 



The star-like figures (plasmatic cells) exist no longer, and 

 cannot be discerned by colouring with carmine and the action 

 of acetic acid. 



What we do observe in these preparations consists of 

 bundles of connective fibres cut across obliquely, or showing 

 their full length ; besides these, cells of a fusiform appear- 

 ance, or resembling those of lamellar pavement-epithelium ; 

 lastly, numerous cells which are round, or of an irregular 

 form. Elastic fibres are distinguished also in these prepara- 

 tions; they are rectangular, or slightly curved. 



In order to discern the cells, and fully to understand 

 their relations, it is better to add nitrate of silver to the gela- 

 tine, according to the method which Chrzonszczewsky has 

 recommended for the study of capillaries (Paris gelatine 

 softened in cold water, and afterwards m^elted, one part ; 

 solution of nitrate of silver, 2 to the 1000, one part). After 

 colouring Avitli carmine and the action of glycerine and formic 

 acid, the cells make their appearance in the neighbourhood 

 of the bundles ; they are flat, very irregular in their contour, 

 destitute of membrane, and they contain a flat and ovoid 

 nucleus. When these cells are seen in profile, they appear 

 fusiform, and their nucleus resembles a rod. Certain of these 

 cells present prolongations, some of which appear to be in 

 relationship with similar prolongations arising from neigh- 

 bouring cells. But this disposition is very rare. 



Good preparations may also be obtained by injecting into 

 the cellular tissue a solution of nitrate of silver (1 to 1000). 

 The portion of tissue in contact with the solution becomes 

 slightly paler, and forms a globular mass filled with liquid. 



