78 



3I0IIBID GROWTH IX GENERAL. 



all these properties are manifested varies directly as the amount 

 of newlj-formod tissue, inversely as the amount of tissue replaced 

 by the morbid products. The loss the quantity of parenchyma 

 which has been used up, the more does the growth tend to 

 squeeze it and to protrude from it. There are knots which, as 



Fig. 31. 



) 



Kaked-eye forms assumed by products of morbid growth : dia- 

 grammatic. The shaded part denotes the normal paren- 

 chyma. «. Uniform swelling of a whole organ; a\. Its 

 normal outline ; h. The knot {nodus) ; c. Infiltration ; d. 

 Growth of a knot by infiltration ; e. Flat intumescence ; 

 /. Tnher ; g. Pajnlla ; li. Fiimjus ; I. Pohjims ; /;. Den- 

 dritic outgrowth (jicqnUoma). 



soon as they have arrived at a certain, and that by no means 

 striking size, cease to grow by extension of the morbid action 

 to the contiguous parenchyma (growth by apposition), and pro- 

 ceed to increase by proliferation at their centre (central growth). 

 The knot then acts almost as a foreign body. The mechanical 

 irritation of surrounding parts, alluded to above, assumes so 



