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A TEXTBOOK OF THEORETICAL BOTANY 



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Fig. 1478. — Ranunculaceae. Floral diagrams. Top left, Aqiiilegia 

 Top right, Aconitum. Bottom left, Ranunculus. Bottom right, 

 Hellehorus. (After Eichler.) 



oil-containing swellings on the raphe. The fruits of some species of Ranun- 

 culus are hooked and are distributed by animals and birds. The seed con- 

 tains copious oily endosperm with a very small embryo, which only develops 

 after dispersal in R. ficaria and Eranthis. 



Pollination is effected either by insects or by wind. The flowers are 

 usually protandrous, but those of Thalictrum and Helleborus are proto- 

 gynous, while those of Anemone and Trollius are homogamous. Thalictrum 

 is wind-pollinated but most of the other genera rely on insects for polli- 

 nation. 



The family contains forty genera and about 700 species, which are 

 distributed in north temperate regions and are well represented in Britain. 

 The plants are mostly terrestrial perennial herbs, but in Paeonia and 

 Clematis they may be shrubby or in the latter genus scrambling climbers 

 with clasping petioles. Tendrils are developed in C. aphylla in which the 

 whole leaf becomes modified and carbon assimilation is limited to the stem 



