Foxglove and Toadflax 253 
The Water Figwort (S. aquatica) is another 
species common in ditches, and on the margins 
of ponds. It is a larger, much taller growing species, 
but otherwise similar in many respects, including 
the arrangements of its flower-parts and its insect- 
visitors. 
The Yellow Monkey-flower (Mimulus luteus), be- 
loved of window-gardeners, though found growing 
apparently wild by riversides in many parts of the 
country, 1s not a native plant, but an introduction from 
North America in 1826, whose minute seeds would 
appear to be adapted for water-carriage. We will 
merely note in passing that the two plates into which 
the stigma is divided are sensitive, and close together 
when touched. ‘This appears to be a precaution 
against pollen falling off when once deposited thereon, 
for the plates immediately close over it. But there 
is no doubt another reason for it, and that is that 
after fertilisation the stigma shall not at all impede 
the bee’s access to the anthers, which stand just 
behind. 
The neat and delicately-fashioned Cornish Money- 
wort (Sibthorpia ewropea) has very minute flowers, 
with a five-lobed corolla of pinkish hue, and four 
stamens. It appears to be fertilised by small flies, 
and is particular to deter creeping insects by 
developing hairs on the tiny round leaves and thread- 
like creeping stems. 
In this family there is a group of no less than six 
native genera distinguished by one common habit— 
they are parasitic upon the roots of other plants. 
They further agree in having the corolla divided into 
an upper and a lower lip, in having but four stamens, 
