THE LIVING SUBSTANCE. 



47 



endosarc, that is, the more hyaline, fluid, colorless portion which 

 does not carry solid bodies or nutritive material in an unassimi- 

 lated state. This is already, in esse as well as in posse, an 

 ectosarcal formation, and may be seen to function in a charac- 

 teristic, organized way as it is mingled with the true endosarc. 

 Besides that hyaloplasm which is formed of the structure of 

 Butschli, there is an interalveolar, hyaline substance, the finer 

 foam, which also flows out with, or besides, this, and the two 

 structures mingle fluidly amongst each other. In such ecto- 

 sarcal outflow, there follows the first impulse a more or less 

 active motion of these alveoli amongst each other. There are 

 so many modifications in individual cases of the result in 

 particular, that it is difficult to seem to describe accurately 

 any one instance, unless to those who hear all are familiar. 



The damming back of outflowing substance by a rapidly 

 effected pellicular formation of ectosarcal character, or by 

 obstruction of already existing pellicle or ectosarc ; as conflict- 

 ing with the onward rush of material from the endosarc, 

 causes often in the newly formed ectosarc a kind of boiling 

 motion which comes to an end variably soon according to 

 circumstances. Where the barrier is an existing ectosarcal 

 formation which does not readily yield to the outflowing sub- 

 stance, the direct course of this is changed to more or less 

 lateral flow. The alveoli of Biitschli's structure then become 

 less freely mingled with one another, as if the impelling force 

 ceased to act, or as if there arose an increased viscosity crossing 

 the path of the latter, or sometimes following it in point of time 

 and impeding the fluid motion. Such viscosity is understood 

 from certain optical changes in the quality and action of the 

 substance, or by changes in structure. There is little doubt that 

 further progress is often checked by formation also of a more 

 finely structured, and therefore more viscid and resistant, area 

 in the advancing substance itself, along the line of its contact 

 with the existing ectosarc ; just as in this latter when it came 

 in contact with the water, a similar area was formed, checking 

 in the same way the substance following fast behind. 



If the outflow of hyaloplasm has burst through an existing 

 pellicular membrane into the water, or runs very close to this, 



