280 STAMINAL ARRANGEMENTS IN POTENTILLA. 
Number of flowers Number of — in 
examined. the fest 
5, 5, 6, 4 k 4 
5* 5,4, 5,4, 4 
2 5, 3 > 3 
& 5 
lf a; 
P. rupestris, L. 
Number of flowers Number of stamens in 
xamined. estoons. 
oH mH 
ot 
e oo 
It would be rash to speculate as to the probable value of the stami- 
nal arrangement in distributing the species of Potentilla into natural 
roups. I scarcely anticipate that it will serve as a basis for primary 
division of the genus, although I have little doubt that it will be found 
of great importance as a means of establishing, or at least limiting, minor 
groups. In a genus so extensive as this, my present contribution 
towards a knowledge of the staminal arrangements can only be viewed 
as a nucleus round which the results of further investigation may be 
aggregated. I therefore hope that auy who have opportunities of 
examining or discovering species in the uem state will carefully note 
the disposition of the stameus. 
In connection with the foregoing, I would call attention to the an- 
dreecium of Nuttallia cerasiformis, which, as is known, consists of only 
15 stamens, viz. 10 age omm and 5 antipetalous (Plate LII. Fig. 4). 
Such ane contrasts most interestingly with the types I have 
described. Thus, in | Nutlallia there are no antisepalous stamens; 
in P. fruticosa, ete., there are no antipetalous stamens; while in 
anserina, ete., iie are both antisepalous and antipetalous stamens. 
* In one of these five flowers a stamen occurred superposed to one of the 
petals, in sition to those in the festoons. 
? I of the sepal to which the festoon with seven stamens was super- 
posed was bifid. 
