88 THE FERTILISATION OF FLOWERS. | PART ILI. 
Acumitum septentrvonale, Koell., has likewise proterandrous flowers, 
figured by Axell (17). 
Peonia Moutan, Sims., according to Delpino, is regularly fertilised 
by Cetonize, which lick the fleshy disk around the carpels. 
REVIEW OF THE RANUNCULACEA, 
While the Umbelliferze form a numerous family where a certain 
sum of adaptations insuring cross-fertilisation has been inherited 
from ancestral forms and descends through all branches of the 
family, in Ranwnewlacee, on the other hand, we have a family 
whose separate divisions have developed for themselves quite 
distinct advantageous modifications. We see conspicuousness 
insured in Ranunculus by the petals; by the sepals in Hranthis, 
Helleborus, Anemone, Caltha ; by both together in Aguwilegia and 
Delphinium ; by the stamens in Thalictrum. Honey is wanting 
in Clematis, Thalictrum, and Anemone: it is secreted by the sepals 
in certain Peonies ; by the petals in Ranunculus, Hranthis, Helle- 
borus, Nigella, Aquilegia, Delphinium, Aconitum ; by the filaments in 
Atragene ; by the anthers in Pulsatila ; by the carpels in Caltha: 
it is sometimes easily accessible, at other times more or less 
deeply hidden. Such a variety of different adaptations is explained 
by supposing many different ways of attaining perfection to have 
been available for the plants when their flowers had not yet been 
modified so far as to insure cross-fertilisation. 
An easily accessible situation of the honey in simple, regular 
flowers carried with it the advantage of abundant insect-visits ; but: 
at the same time the objection that the visitors crept about the 
flowers in various ways, often accomplishing only self-fertilisation, 
often leaving the flower still unfertilised. Honey more deeply 
placed, brought the disadvantage that a great multitude of 
insects were shut out; but this advantage, that the bees with long 
proboscides had to move in a particular way to reach the honey, 
and so stamens and pistils could in a simple manner be arranged 
so as to render cross-fertilisation inevitable. We find self-fer- 
tilisation possible in all regular Ranunculaceous flowers with 
easily accessible honey; but prohibited by well-marked proter- 
andry in all those with deeply situated honey, whether regular, as 
1 Lists of visitors to the following additional species are given in my Weitere 
Beobachtungen, pt. i.: Clematis Vitalba, \., Thalictrum minus, L., Hepatica triloba, 
Gil., Pulsatilla vulgaris, Mill., Anemone silvestris, L., A. ranunculoides, L., Adonis 
vernalis, L., Myosurus minimus, L., Actea spicata, L. 
