ABSORPTION A METAMORPHIC PROCESS. S'J 



portance, and substantially refers it to imperfectly- 

 absorbed remains of embryonic and previously-formed 

 tissues. " Every adult organ may be said to contain 

 skeletons of organs which TV ere active at an earlier 

 period of life " (" Biopl.," 105). The function of ab- 

 sorption thus belongs to the metamorphic part of the 

 developmental process, and the proof of this is given 

 by the fact that the connective tissue is almost com- 

 pletely absent in insects, in which, as is well known, 

 the metamorphic process is most complete. Here the 

 organs and textures of the larva are entirely removed 

 by the masses of germinal matter which are destined 

 to form the imago. These masses "absorb, remove, 

 and, in fact, live at the expense of the tissue which is 

 to disappear; and whether this change occurs physio- 

 logically or [in other organisms] pathologically, the 

 process is essentially of the same nature " (" Croonian 

 Lecture," p. 265). In a similar way, temporary mus- 

 cular fibres are first produced and absorbed ; temporary 

 kidneys and other temporary organs of embryonic 

 life illustrate the same process. In disease this ab- 

 sorptive faculty maybe exalted and the reparative one 

 destroyed. " In those changes which lead to the forma- 

 tion of pus, the removal of every texture is as perfect 

 as during the pupa state of an insect, but the bioplasm 

 constituting the pus corpuscles has no power to give 

 rise to that which will take part in the development of 

 new tissues " (" Biopl.," p. 106). I may conclude this 

 subject with the absorption of bone, which illustrates, 

 in a striking way, the function of the protoplasm in 

 this process. 



