DERIVATION OF THE FLORA AND FAUNA 407 



polystachyus Rottb. Trop.-subtrop., wide-spread. 



cylindrostachys Boeck. As the former. 



brevifolhis (Rottb.) Hassk. Pantrop. 

 Scirpus L. 



ripariiis Presl. N. Amer., Calif, to S. Amer., south to Fueg., Falkland. I can- 

 not find that var. paschalis Kiiekenth. deserves to be distinguished. 



Juncaceae. 



J uncus L. 



plebeius R. Br. Colomb.-Urug., Austral, Tasm., N. Zeal. 



Piperaceae. 



Peperomia Ruiz et Pav. 



rejlexa Dietr. Pantrop., very widespread, north to Hawaii and south to 

 N. Zeal.; also on Rapa and possibly Pitcairn. 



Chenopodiaceae. 



Chenopodiiim ambiguiun R. Br. Austral., Tasm., N. Zeal. 



Polygonaceae. 



Polygo7imn L. About 150, world-wide. 



acuminatum H. B. K. W. Ind., Centr. and S. Amer., Galap. Is., trop. and 

 S. Afr., Orient. 



Nyctaginiaceae. 



Boerhaavia L. About 20. Pantrop. 



diffusa L. Widespread in the Pacific and a common weed in the Old and 

 New World; probably of aboriginal introduction. 



Aizoaceae. 



Tetragonia L. 



expansa Murr. 



Cruciferae. 



Nasturtium R. Br. About 50. Widespread, mostly temp. 

 sarmentosum (Sol.) O. E. Sch, Austral.-Polyn., Hawaii. 



Leguminosae. 



Caesalpiiiia L. At least 90-100; pantrop. 



bonduc (L.) Roxb. Trop. As.-Polyn. 

 Soph or a L. 



toromiro (Phil.) Skottsb. Nearly related to the species from J. Fern. 



Euphorbiaceae. 



Euphorbia L. 1 500-1600; world-wide. 



hirta L. Indomal.-Polyn., often adventitious. 



serpe7is L. As the former, also common in trop. Amer. 



