THE BEGINNINGS OF LIFE. 451 



which was kept at a temperature of 85 90 F in a 

 developing oven. After twenty-four hours the groups 

 and single Desmid-like bodies were still seen under- 

 going partial rotations, and the number of Bacteria 

 had increased in quantity. After forty-eight hours, 

 a group of eight cells, in addition to solitary and smaller 

 groups, was seen distinctly oscillating ; and there were 

 two or three elongated bodies (containing segmented 

 blocks of protoplasm), which seemed to have resulted 

 from the development of single organisms ; there were 

 also several Leptothrix filaments, and a great increase 

 had taken place in the number of Bacteria, which showed 

 very active movements of translation. After this period 

 the contents of the Desmid-like bodies began to fade, 

 and they seemed gradually to die ; though the Bacteria 

 lived and increased for several days, during which the 

 specimen was kept under observation. 



Experiment k. A solution containing ten grains of 

 ammonic sulphate, and ten minims of dilute liquor 

 ferri perchloridi in one ounce of distilled water. 



A thick scum formed on the surface after about two 

 months. The flask was opened at the expiration of the 

 third month, the vacuum being still well preserved. 

 On microscopical examination, no trace of living 

 things was to be seen amongst the amorphous deposit 

 at the bottom of the flask. The pellicle was found to 

 present a cellular arrangement (Fig. 39). It polarized 

 light, however, and was obviously crystalline in con- 

 stitution. It was very heavy sinking at once in the 

 eg 2 



