482 



hitherto doubtful. The extent to which animalcules of the 

 classes Monadina and Vibrionia become developed is almost 

 incredible, — thousands of them will be found to cover the field 

 in specimens examined from most different sources ; they are 

 present at very early periods, probably within twenty-four 

 hours in some cases, and in the oldest rotting tissues which I 

 have examined I have discovered them. I may, however, re- 

 mark that there are some intermediate stages which I cannot 

 as yet in any way define, at which their development ceases, 

 no trace of animalcule motion being observable. 



"Besides the larva of insects familiar to all observers, cer- 

 tain forms of articulata likewise present themselves. I have 

 as yet met with only a form of annelida, most nearly (as I be- 

 lieve) allied to Polia siphunculus, which is visible to the naked 

 eye, and under the microscope exhibits a very beautiful inter- 

 nal structure. I have observed two varieties, differing slightly 

 in size and some other particulars ; they appear to occur in- 

 differently in all situations. 



" In the debris of these animalcules, when dead, and under- 

 going histolytic changes, will be found the nucleated bodies 

 I before described,* as 'peculiar elements.' To recognise 

 these and other elements thus liberated, requires that the 

 living animalcule forms should be carefully studied, and this 

 becomes therefore a necessary preliminary step in the general 

 study of Histolysis, which will be considered at length in its 

 proper place. In the construction of the Histolytic Scale, 

 therefore, in order properly to represent the actual succession 

 of phenomena it will be necessary to insert an ascending line 

 to indicate the period of development, and the growth of ve- 

 getable and animalcule forms ; and to indicate their subsequent 

 decay and dissolution a second line must be drawn from the 

 summit of the first to the first grade of the Histolytic Scale, 

 showing that these elements now fall in with the general process 

 of decay. 



* Proceedings, ante, p. 456. 



