PATHOLOGICAL AND EMBRYONIC NEW-FORMATION. 44! 



cisive. From the moment that I was able to maintain 

 that there was scarcely any part of the body which did 

 not possess cellular elements that I could show that 

 bone -corpuscles were real cells, and that connective 

 tissue in different places contained, now a larger, now a 

 smaller, number of really cellular elements from that 

 moment germs in abundance were supplied from which 

 new tissues might possibly be developed. In fact, the 

 more the number of observers increased, the more dis- 

 tinctly was it shown, that by far the greater number of 

 the new-formations which arise in the body proceed from 

 connective tissue and its equivalents. From this rule 

 comparatively few pathological new-formations are ex- 

 cepted, and these belong on the one hand to the class of 

 epithelial formations, and on the other are connected 

 with the more highly organized tissues of a specific, ani- 

 mal (p. 55) nature, for example, the vessels. We may 

 therefore, with trifling restriction, substitute for the plastic 

 lymph, the blastema of the earlier, the exudation of the 

 writers, connective tissue with its equivalents as the common 

 stock of germs (Keimstock) of the body, and directly 

 trace to it as the general source the development of 

 new-formations. 



If we take a definite internal organ, for example, the 

 brain or the liver, it was scarcely possible, as long as 

 people saw nothing more than nervous matter in the 

 brain, and admitted the existence of nothing more than 

 vessels and hepatic cells in the liver, to imagine the oc- 

 currence of a new-formation in them without the inter- 

 vention of a special formative matter. For it was of 

 course easy to convince oneself that new-formations do 

 not in the liver usually proceed from the hepatic cells or 

 the vessels. And that in the substance of the brain, the 

 nerves as such do not give rise to new-formations, has 

 been known ever since the microscope has been em- 



