Foxglove and Toadflax 261 
two-lipped. The upper portion is in truth more in 
the nature of a hood within whose vault the stamens 
are hidden. In the front border of this hood in the 
Common Lousewort (P. sylvatica) there are two tooth- 
like lobes, and between them the style protrudes. 
The filaments keep to the sides away from the 
opening, and the edges of the corolla above the 
junction of the lower lip are curled outwards and set 
with sharp teeth, which indicate to the bee that the 
proper entrance lies elsewhere. 
A remarkable feature is to be noticed in the lop- 
sided way the lower lip is set on the corolla. A 
casual observer might be pardoned for supposing he 
was looking at a deformed flower, yet he would find 
all the specimens he could gather were equally askew. 
The object of it appears to be to provide a platform 
useful to bees of different sizes in enabling them to 
reach the legitimate entrance—where the edges of the 
corolla are smooth—and so to bring their heads in 
contact with the stigma. A bee alighting on the 
oblique platform has to put his head into the entrance 
sideways, and this is just the method most suited to 
effect his purpose—that of reaching the honey. But 
this pressing-in forces the revolute edges somewhat 
apart, and so alters the position of the toothed lobes 
above that they force the lower edges of the anthers 
slightly apart, and the pollen falls on the bee’s head. 
Bees with very long tongues have merely to push their 
heads just within, but others have to get farther in. 
The smaller bees are excluded by reason of the long 
tube; but some of those which cannot reach the 
honey legitimately bite holes in the corolla low down, 
and thus achieve their object. The calyx in this 
