1895.] Flowers and Insects. 147 
remarkable for their close mutual relation with two bees of 
the genus Colletes. As far as known, Heuchera hispida’ is 
the only other flower adapted to a bee of this genus. On 
twelve days, between May 29th and Sept. 21st, I found the 
flowers to be visited by these bees and by no other in- 
sects, except the Ha/zctus taken on P. Virginiana. 
have taken single females of Colletes latitarsis on flowers 
of Asclepias incarnata (entrapped and dead) and Polygonum 
hydropiperoides. Both sexes are abundant on Physalis, and 
the female seems to depend exclusively upon the pollen of 
these flowers. 
I have taken Colletes willistonii on flowers of Rhus glabra 
and Melilotus alba, but have never seen it collecting any pol- 
len except of Physalts. 
93. £. alkeheng t, 
pubescens, nectar-glands, guides, etc.—(z) Kirchner, Neue Beobacht- 
en ii i i 
MIMULUS RINGENS L.—The flowers of Mimulus are homog- 
amous. Bees entering the corolla first touch the stigma, 
which closes up and exposes the anthers behind it. Self-pol- 
lination occurs in M. luteus, but Darwin (13) found that pol- 
len from another plant was prepotent over the flower’s own 
ollen. He saw &M. roseus visited by bees. According to 
Batalin (6) M. guttatus is visited by bees. 
The irritability of the stigma of Mzmu/us was well known to 
Kurt Sprengel (1), Braconnot (2) and Vaucher (3). “The at- 
ter mentions it as occurring in M. /uteus and glutinosus, and 
supposes that it occurs in other members of the genus. his 
has been verified to such an extent that now it seems that a 
Mimulus without an irritable stigma would be a desideratum. 
Delpino (4,7) was first to indicate the advantage of the 
movement in facilitating cross-pollination. 
In the case of Mimulus ringens, Meehan (17) states that the 
stamens dehisce and the stigmas generally show pollen before 
the flowers are quite open. He observes the movement of 
7Bot. Gaz. 17: 178. 1892. 
