1918] DEVRIES—MASS MUTATIONS 4II 
The percentage figure for type R conforms to the formula of 
Mendel for monohybrids, assuming the initial rosettes to be domi- 
nant over their absence, but in the cross of O. grandiflora with 
O. biennis the reverse was the case. Possibly the linkage was 
TABLE VIII 
SECOND GENERATION OF ovata 
Cross PBirmioes fh ovata R “ig L Total 
O. grandiflora x Lamarckiana........ 1916 46 14 9 ° 69 
O. Lamarckiana X grandiflora... ..... 1916 60 19 2 ° 81 
O. grandiflora Xnanella.............. 1915 59 13 4 I 77 
O. grandiflora Xnanella.............. 1916 50 16 ° ° 66 
O. oon eager eee IQI5 6 fe) I 51 
©. lata Xerandifiora. 20000 1916 45 16 2 ° 63 
O. gad hon: ochracea X Lamarckiana| 1916 39 27 6 ° 72 
O. grandiflora ochracea Xnanella... . . 1916 3 23 I ° 77 
ey a ee 306 | 134 | 24 556 
Portsicace Nay Peee ae CLL ee eee ee ee 71 4 OS] ss. oss 
TABLE IX 
THIRD GENERATION FROM ovala 
Sxcomns ‘THIRD GENERATION 
Cross GENERA- TotTaL 
i one): 2 T L 
O. nanella X grandiflora.............. ovata a7 25 ° fe) 62 
ec Oe ee R ° 29 ° ° 29 
O. grandiflora Xnanella.............. R ) 20 ° ° 20 
# Sag ger a oer ine R ) 79 ° ° 79 
of ae eee of ° 31 36 ° 67 
“ LAER ORS 7 ° 3 | 45 o | 48 
" Oe ee cy ? ° 6 ° 52 58 
f foe ee ee i ° 8 o | 62 70 
WOME Se A a | Bee ate ie | 37° | 208 8x | 114 | 433 
different in the two instances. In these second generations I self- 
fertilized some individuals and cultivated their offspring in 1916. 
Table IX gives their offspring. This gives a percentage of 42 for 
the splitting off of type R from the others, and this figure seems to 
be analogous to the one deduced from our previous table (24 per 
cent). Apart from this splitting, the types T and L had a uniform 
progeny. The third generation of ovata repeated the constitution 
of the second in its most essential points. 
