DICOTYLEDONS 211 



of the Choripetalse are the Calycifloras, so called from 

 the fact that the sepals are united into a tubular or 

 cup-shaped calyx upon whose margin are inserted the 

 petals and stamens. Very commonly the floral axis is 

 prolonged into a tube which may be completely grown 

 to the ovary at its base, so that the ovary becomes " in- 

 ferior," as we have seen to be the case in the higher 

 Monocotyledons. Much the commonest number for 

 the sepals and petals is five, although some families 

 show regularly four, e.g. the Onagraceae (fuchsia, 

 evening-primrose, etc.), and occasionally the number 

 is indefinite (Cactacese). The number of stamens in 

 the Calyciflorse is occasionally the same as the petals, 

 but usually either double the number, or still more 

 numerous. 



The order Rosiflorae, which is subdivided into several 

 families, is one of the largest and most familiar groups 

 of the Calyciflorse. In some of these, e.g. the straw- 

 berry, the carpels are quite separate, while in others, 

 e.g. apple and pear, they are more or less completely 

 united, and there is an approach to an inferior ovary. 



The myrtle family (Myrtacese) is mainly tropical. 

 The petals are often wanting, but the numerous sta- 

 mens, which are white or red, are very conspicuous and 

 serve to attract insects just as showy petals would do. 

 The ovary is here inferior, and the tissues of the calyx 

 may become fleshy and edible in the ripe fruit, as in 

 the pomegranate or guava. 



The Aralia family and the parsley family (Umbelli- 

 ferse) are two related families of the Calyciflorse, which 

 are not, however, very clearly related to the others. 

 Of the former the common ivy (Hedera) and the sev- 



