Ficaria verna , and other Members of the Ranunculaceae. 73 
In addition the orientation of the supernumerary petals is quite con- 
sistent with their origin by fission (cf. Fig. 16, F, P4 and P5). 
Number of Sepals. 
4 
5 
6 
7 
8 
9 
10 
Total number of specimens 
Table X. 
Ranunculus bidbosus. 
Number of Petals. 
5 6 7 8 9 10 
10 7 3 4 
621 — 
1 — 1 — 
11 
1 
= 
A very significant feature, which emphasizes not only the distinction 
between calyx and corolla but also the essentially foliar character of the 
former, is the fact that in three out of the fourteen flowers with extra 
sepals, the number of peduncular ridges cor- 
responded to the number of calyx segments. 
But in no case were additional ridges present 
when the sepals numbered five whatever the 
increase might be in the number of corolla 
segments. Coloured sepals are occasionally 
met with (cf. Leavitt, 1909). 
(c) Ranunculus acris . Seventy flowers 
of this species were dissected and showed 
a wide range of variability as regards the 
number of parts present. The minimum 
observed was seventy-nine and the maximum 
275. The sepals varied in number from five 
to twelve, the petals from five to thirteen, 
the stamens from forty-four to 167, and the 
from fourteen to eighty-three. Such 
extraordinary fluctuation would necessitate 
the examination of a far larger number of 
specimens before any conclusions could be drawn regarding the existence 
of any trimerous or pentamerous tendency. But the data are sufficient 
to show that each region tends to vary meristically in the same sense. In 
the extreme example referred to above the floral formula was K 12, C 13, 
A 167, G 83. In no instance was an increase in the number of sepals accom- 
panied by a decrease in the number of petals. Evidence for the origin of 
supernumerary petals by fission is afforded by the occurrence of cleft or 
trilobed corolla segments. Petaloid stamens were observed in a few 
Fig. 20. Stamens of Ranunculus 
auricomus ,var. depauperata , developed 
in place of the petals. 
