3158 Profs. Percy Frankland aud Marshall Ward. 



from the insolated tube showed three colonies only on the third day, 

 and these were very small, more densely granular, and irregular in 

 outline than the normal colonies, and showed no traces of lique- 

 faction even on the fourth day. On the fifth day the liquefaction 

 was beginning, but even after fourteen days one of the three colo- 

 nies was only just breaking up. 



The stab-cultures gave similar results. Those from the darkened 

 tube showed a distinct thistle-head funnel of liquefaction in three 

 days, whereas the feeblest signs that infection had really occurred 

 were all I could get in the same time from the insolated cultures. 



Here, again, however, the two sets of tubes gradually become 

 alike, evidently because the at first enfeebled cells gradually re- 

 gain their vigour, and once more rapidly peptonise the medium. 



The experiments with water were repeated on October 12, all the 

 arrangements being as before. 



The exposed tube was out from 9 A.M. to 3 P.M. in brilliant sun- 

 shine the whole time practically. 



After three hours' exposure, a plate was made. That from the 

 dark tube showed colonies, visible only under the microscope, in 

 nineteen hours, and in two days the whole of the gelatine was 

 liquid like water. 



The plate from the lighted tube showed no signs until the third 

 day ; on the fourth day six colonies had made their appearance, but 

 these only began to soften the gelatine around some days later, and 

 even on the twelfth day two of the six colonies were still circular 

 depressions, though the other four had liquefied the gelatine some 

 distance round. 



After six hours' exposure, further plates were made from the above 

 tubes on October 12. 



As before, colonies were visible with the lens on the plate made 

 from the dark tube in sixteen hours, and before the end of the second 

 day the whole of the gelatine was liquefied like water. 



On the plate from the light tube five slowly-developing colonies 

 had appeared by the fourth day, one of which showed feeble signs of 

 liquefaction next day. But even after twelve days only three of 

 these colonies were vigorously liquefyiug the gelatine, the other two 

 being still compact and circular, though one of them lay in a slight 

 depression. 



Stab-cultures were also made at the end of the six hours' exposure 

 on October 12, with the results as before. In the case of the culture 

 from the dark tube, the funnel of liquefaction had reached the walls 

 of the tube, and liquefied one-eighth of an inch of gelatine in four 

 days, whereas that from the lighted tube, in the same period and 

 side by side, had not even begun to liquefy the gelatine, though the 

 infection had taken. 



