PART I.] Observations on an Ordinary Alvine Discharge. 35 



one exceedingly of corn in a miller's hopper. This lasted for twenty minutes, when 

 suddenly all movements ceased ; the halo and vacuole disappeared, its outline became 

 irregular and undefined (2, 3) ; finally, although the eye was constantly observing it, all 

 trace disappeared, and no distinction could be observed between other molecules in the 

 field. The remaining amoebae seem to have undergone the same change, for when the eye 

 was removed from the particular one described, none could be found, except a few empty- 

 looking ones. I have frequently observed exactly similar phenomena occur in the so-called 

 salivary corpuscles. No further change occurred in the slide, nor was there a return to the 

 former condition during the succeeding week. 



In the watch-glass the animalculse continued to increase and multiply, but other kinds 

 did not appear. The glass was held over a spirit-lamp and the liquid boiled, in order to 

 see if out of their dead bodies others of the same or of another kind would appear ; but 

 none did, and at the end of a fortnight the experiment was brought to a close. 



Illustration III. : — 



The ordinary stool, to which allusion was made at page 27 as containing such 

 quantities of the animalculse in the " still " and active condition, was kept under observation 

 for six weeks. 



A slide was taken and two minute portions were placed side by side, a distance of 

 about half an inch intervening, and circular covering glasses applied of the same 

 diameter. 



During the first, second, and third days the changes which occurred were alike in the 

 two preparations. The oil globules gradually disappeared, the circular, " still " condition 

 of the animalculae became at first granular, ceased presenting the amoeboid projections, the 

 latter being frequently not retracted, but trailed along as they rolled under the glass ; the 

 general appearance of the altered slide being represented at Plate XVI, Fig. Ixiii, 

 the earlier condition having already been described, and is figured at Ixii. 



The movements of the active little entozoon became more and more sluggish ; 

 at the same time it became granular and circular, and finally disappeared altogether, 

 probably passing into the " still " condition, which also gradually disappeared. The 

 two preparations now" assumed different appearances. 



(a) On the fifth day some fungi were seen to develop in one of the preparations, 

 which may be designated — a; long filaments of oidium lactis, as figured at xxiii, 

 commenced spreading over the entire preparation, and in the midst of the molecules 

 (which had also undergone various stages, as already described in the first illustration) 

 little " heaps " were forming of precisely the same microscopical characters as are 

 given at page 32 and other places. On the sixth day a few molecules in the midst 

 of the heap had increased in size, and on the eighth day nearly every heap was 

 covered with yeast cells, in conjunction with very minute anguillulse (?) (Plate XIX, 

 Fig. Ixxix). 



