168 
POPULAR SCIENCE REVIEW. 
The Scarlet Kunner is one of the very few plants on which 
I have found time and opportunity to experiment. Having' 
covered a large portion of a plant with gauze so as to exclude 
the visits of bees, I found that out of a vast number of blossoms 
thus protected not a single one produced a pod, while the 
unprotected blossoms were for the most part fruitful.* Even 
of unprotected blossoms a very considerable proportion failed to 
produce pods — a much larger proportion, I think, than is the 
case with most flowers. This is probably due to the fact already 
mentioned, viz. that most bees have learnt to get at the nec- 
tary by nipping the tube. I have more than once watched for 
a considerable time without seeing a single bee visit the flowers 
in any other way. Were all bees equally clever, there would 
be an end of Scarlet Eunners ; unless indeed either nature or 
artifice were to induce some modification of structure — such as 
the large calyx of Pedicularis — by which the tube might be 
protected, and the bees again driven to the mouth. 
Very similar to the Papilionaceous flowers are the Fumitories* 
as regards the mechanism for their fertilisation. Here again, 
two of the petals are partly united so as to form a receptacle, 
in which are lodged the reproductive organs (fig. 7). The 
arrangement of the other two petals is such that an insect, in 
order to get at the nectary, is forced to light on this receptacle, 
which is expanded laterally so as to form a convenient landing- 
place. When the insect is so placed, its weight causes the 
receptacle to sink, and the reproductive organs issue from their 
hiding-place and strike the insect on its under surface. Here 
also the emergence of the organs is due sometimes simply to 
the descent of the receptacle, and sometimes is assisted by a 
tendency of the elastic style and stamens to spring upwards. 
The next and last flowers I shall deal with are some in which 
the anthers alone are irregular. Everyone knows the cross- 
leaved Heath ( Ericatetralix ), so common on boggy mountains* 
This has a corolla (fig. 8) which may be roughly described as 
bell-shaped, and which hangs when expanded, as a bell should, 
with its mouth more or less downwards. The style will stand 
for its clapper, but with this difference, that it reaches to the 
very mouth of the bell, or even projects slightly, when it termi- 
nates in a semiglobular stigma. The viscid surface of this 
A similar experiment, however, which I made on the Kitchen-garden 
Pea ( Pisum sativum) gave a very different result. The protected flowers 
formed pods as well as the unprotected. The Pea, then, is capable of self- 
fertilisation, without the aid of insects. This, however, does not exclude 
the probability of more or less frequent intercrossing ; and it seems to me 
impossible to suppose that the Pea should possess, without any’purpose, a 
mechanism which in other Papilionaceous flowers, as Phascolus , &c., has a 
distinct use. 
