379 



Berlin, relying upon the systematic conception of Reicliert, 

 and upon the observations related at the beginning of this 

 "Nvork, has identified bony tissue with connective tissue. But 

 at the present time, since the works of H. Miiller upon the 

 development of bone, this identification is no longer admis- 

 sible. The facts related in this memoir show that there are 

 further some fundamental morphological differences between 

 bony tissue and connective tissue. BetAveen the structure of 

 tendons, for example, and that of the bones which are their 

 substitute in birds, there is no analogy, and the cellular 

 elements are grouped in an entirely different manner in these 

 two kinds of tissue. Histologists who maintain that in a 

 chicken the tendons in becoming bony undergo a simple 

 calcareous infiltration, have been deceived by the delusion, 

 caused by transverse sections. I have undertaken to inves- 

 tigate this subject, and the facts at which I have arrived will 

 form the material for another work. 



In conclusion, I must remark that the cells of connective 

 tissue have not the fixity which Virchow believed them to 

 have. They are not enclosed in resisting substance ; further, 

 they have no truly specific character; in many respects, 

 they resemble the white blood-globules, or embryonic cells, 

 and are free between the bundles of tissue. Also the rapidity 

 with which, under the influence of an irritant, globules of 

 pus are produced in connective tissue, is truly prodigious. 

 In inflammation, the white globules escape from the vessels 

 and disperse themselves in the sj)aces left between the fibres, 

 but it is easy to observe the division of the pre-cxistent 

 cells. ^ It also seems that in a slow movement, such as that 

 which is produced around a simple wound, all the work that 

 is done depends upon the constituent cells of the tissue. 

 Moreover, these cells, once modified by irritation, form masses 

 of embryonic tissue, at the expense of which a new tissue 

 will be formed according to the nature of the pathological 

 movements. 



If connective tissue easily yields pathological new forma- 

 tions, it is simply because some of these cellules are em- 

 bryonic and others closely allied to this state. But the 

 property of engendering these new formations does not 

 belong exclusively to the connective tissue. It suffices that 

 the cellular elements of a tissue are able to return to the em- 

 bryonic state, for them to take a part in certain cases in the 

 formation of pathological tissues. 



' Dr. Ranvier is here in accord with Professor Strieker, regarding neither 

 Virchow's nor Cohnheim's view as the whole truth. — Ed. Q. J. M. S. 



