366 



Profs. Percy Frankland and Marshall Ward. 



It was perfectly clear that, exposed at the same temperatures, the 

 culture from which the blue rays were screened flourished well and 

 formed spores, whereas the other was starved and retarded, and 

 could scarcely form spores at all. 



Spores sown as before, in weak gelatine, at 8.30 A.M., July 7, were 

 at once exposed to the south window. At 9.30, however, I removed 

 them to the upper room, north window, to avoid high temperatures. 



The day opened very bright, with a deep blue sky, about half 

 covered with cumulus clouds, at noon became more overcast, and after 

 1 P.M. was dull and quite overcast ; rain later. 



Water. 



At 3 P.M. I selected a good rodlet for measurement. 



Curve 63, p. 368. 

 Doubling periods : 



12 -5 25 n = 3 P.M. 4.12 P.M. = 72 minutes at 20 '52120 -5 C. 

 25 --50 ,, = 4.12 5.5 - 53 20 '5 19-5 C. 



50 100 = 5.5 6.46 = 101 19 -5 19 C C. 



Reckoned back : * 



135 67 '5 fi = 5.40 P.M. 7.40 P.M. = 120 minutes at 2018 C. 

 67 '5 33 -75 = 4.30 5.40 =70 20 '5 20" C. 



33 -75 16 -75 = 3.44 4.30 = 46 21 20 '5 C. 



* I.e., the doubling periods calculated back on the curve from the last observa- 

 tion instead of forwards from the first one, and thus giving comparisons of the 

 growth in different sections of the filament. 



