354 SYSTEMATIC BOTANY 



terminal or axillary, the flowers regular, with five 

 sepals, five petals, and five stamens connected together 

 and to the stylar-head, and usually with outgrowths 

 forming the staminal-corona. There are two free car- 

 pels, which in fruit form follicles and the seeds are 

 flat with a tuft of hairs (fig. 58). 



The family is a fairly large one and almost ex- 

 clusively tropical, being unknown wild in temperate 

 regions. There are, of course, differences between the 

 genera, the most important of which is in the position 

 of the translator, which may be at the top so that 

 the polliniums hang down as in CALOTROPis, or at 

 the bottom so that they are erect, or so that they lie 

 horizontally. In some genera there are twenty polli- 

 niums, i.e. two to each anther lobe. There are great 

 differences too in the form of the corona, which may 

 be single as in CALOTROPIS or double. In the family 

 are also included genera, like CRYPTOSTEGIA, in which 

 the filaments are free, and the pollen masses granular 

 not waxy, but which are in other respects much more 

 like this family than to the closely allied APOCYNACE^E. 



The Wax-flower, HOYA CARNOSA, Br., is often culti- 

 vated for its flowers. The corona is a very large, 

 thick, stellate, white mass. Another species, * H. 

 OVALIFOLIA, W. & A., grows wild on the hills. 



STEPHANOTIS is a well-known garden plant, belong- 

 ing to this family, as also is CRYPTOSTEGIA which has 

 giant bell-shaped flowers. 



CARALLUMA and SARAOSAEMMA have no leaves but 

 instead green branches, a typical adaptation for a dry 

 climate. Compare EUPHORBIA TIRUCALLI, L. (p. 379) 

 and the Prickly-pear (p. 181). 



