155 



R. virgata Weh., this cannot be decided without the introduction 

 of living plants. 



Rhipsalis comorensis Web. and R. zanziharica Web. become 

 synonyms of R. Cassutha Gaertner. 



How could the American species of Rhipsalis become trans- 

 ported to Africa? Evidently by migratory birds. I see here 

 birds which devour the berries of Rhipsalis entire. They are 

 small, very glutinous, full of a sweet pulp, in which are small 

 seeds, variable in number according to the species. They are 

 not dehiscent, but at the end of two years decay and fall off at 

 the least contact. When Rhipsalis is situated where small birds 

 have access to it, it Is stripped of its fruit as soon as they ripen. 



We can admit at first sight the function of the intestines in the 

 propagation of seeds. W^e have seen seeds of figs deposited on 

 the summits of date-palms, where they root in the earth which 

 collects in the axils of the leaves. The coat of the seeds in 

 Rhipsalis has a hardness analogous to that of the seeds of Ficus 

 Carica. The birds could also carry the seeds on their feet or on 

 their feathers, where they would adhere for a long time. The 

 berry, half rotten, very readily caducous, could also attach 

 itself entire to any object which it touched. 



It is to be noted that no species of the group of flat-jointed 

 Rhipsalis {Alatae) has been found in Africa and that the species 

 of this group almost all have the seeds very fragile. The pulp 

 of their berries is generally not very adhesive. These two char- 

 acters render very dubious their arrival in good condition after 

 the long journey across the Atlantic. 



No botanist has ever doubted the importation from America 

 of the Opuntias which are naturalized throughout Central Europe, 

 also in all of Africa and in certain Asiatic regions. No Opuniia 

 found in the Old World has received the honor of a specific name. 



It seems very plausible that this genus also has been propagated 

 or distributed by birds having scattered the seed which have 

 very bony hard coats and are very durable. 



Larger animals and man himself have contributed largely to the 

 distribution of these plants, of whi'ch the fruits are edible, if not 

 all of good quality. 



