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a bundle completely surrounding and overtopping the pistil, as 
represented in a and 6, the anthers being in the act of discharg- 
ing their pollen in h. At a later stage, c, the empty anthers are 
bent down out of the way of the stigmas, which are even 
yet not in a receptive condition ; this latter state being repre- 
sented at d. Spontaneous self-fertilisation is in this case scarcely 
possible. In the smaller species (Malva rotundifolia) the 
structure is the same up to a certain point, but the stigmas 
mature earlier, and when in this condition coil themselves 
among the anthers, as represented in e, there being still suffi- 
cient pollen left in the anthers to ensure the self-fertilisation 
of the flower. The two species often grow intermixed ; both 
are scentless ; insects are, however, abundantly attracted by the 
large showy flowers of M. sylvestris, which are also beautifully 
streaked, the streaks all pointing towards the nectar-glands 
(n in a), at the base of the tube formed by the filaments. The 
flowers of 31, rotundifolia are much smaller and of paler 
colour and are not streaked, and hence not so attractive to 
insects. Dr. Muller records thirty-one species of insects, chiefly 
Hymenoptera, which he detected visiting the former, whilst only 
four were observed to frequent the latter species. 
Our fig. 2 is a very good illustration of a necessarily cross- 
fertilised flower. Bianthus deltoides, the “ maiden-pink,” is 
scentless ; but each of the five petals is provided with a number 
of purple spots, which seem to indicate to the butterflies, by 
which they are chiefly visited, the exact place wherein to insert 
their proboscis in order to reach the honey-glands, indicated 
at n in c. The anther, at this time discharging pollen, is 
placed immediately over each petal, and the butterfly cannot 
fail to carry ofl* some of the dust on its head. A second inner 
row of five stamens, at this period completely concealed within 
the tube of the corolla, do not mature till later ; and it is only 
after all the anthers have dropped off that the two stigmas, 
previously coiled round one another, separate and develop 
the hairs which serve for the detention of the pollen, as shown 
in d. 
While the various contrivances connected with the arrange- 
ments of the male and female organs have been more or less 
known to botanists for three-quarters of a century, very little 
attention has been paid, until the publication in the present 
year of Prof. Muller’s book already mentioned, to the corre- 
sponding adaptations of the structure of insects for the same 
purpose. This naturalist — an accomplished entomologist as 
well as botanist — has made this branch of the subject his special 
study, and has collected together a large number of interesting 
and curious facts. There are two ways in which chiefly insects 
perform their part in the fertilisation of flowers — in their 
