美洲大戟亚属 mei zhou da ji ya shu

Agaloma Rafinesque, Fl. Tellur. 4: 116. 1838.

Herbs, shrubs or trees. Leaves alternate, opposite, or whorled; stipules present but small. Cyathia often in terminal pseudumbel; cyathophylls conspicuous or not; glands with petaloid appendages.

About 110 species: North and South America; two species (introduced) in China.

This subgenus comprises a large group of New World species that have usually conspicuous petaloid gland appendages but are otherwise very variable, some ± intermediate with Euphorbia subg. Chamaesyce and others approaching Poinsettia. Some species are grown as ornamentals and have escaped.

Lower Taxon

• Euphorbia marginata Pursh