31 l] FLORA OF COLUMBIA AND VICINITY 169 



234. EUPHORBIA L. ICHAMAESYCE S. F. 

 Gray: DICHROPHYLLUM Kl. & Garcke: 

 TITHYMALOPSIS Kl. & Garcke: TITHY- 

 MALUS Adans.: POINSETTIA Graham]. 

 Spurge. 



592. E. nutans Lag. [E. Preslii Guss.: C. nutans (Lag.) 

 Small]. 



Fields and thickets, especially along streams; common. 



All North America east of the Rocky Mountains except 

 the far north: introduced into Europe and the Madeira 

 Islands. 



593. E. maculata L. [C maadata (L.) Small]. Purslane 



SPURGE. 



Very common in fields and waste places. 

 North America. 



594. E. humistrata Engelm. \C. hmnistrata (Engelm.) 

 Small]. Spreading spurge. 



Waste places; locally abundant. 



Quebec to New York, Mississippi and Kansas. 



595. E. marginata Pursh \p. tnarginatmn (Pursh) Kl. & 

 Garcke]. 



Waste places; scarce about Columbia, but common at 

 Providence. 



Minnesota to Colorado and Texas; introduced east- 

 ward. 



596. E. COrollata L. {Tithymalopsis corollata {l^) Small]. 



Flowering spurge. 

 Common in fields and thickets, especially in light soil. 

 Massachusetts to Ontario and Minnesota; Florida to 

 Kansas and Texas. 



597. E. dentata Michx. \P. dentata (Michx.) Small]. 

 Along streams and in waste places. 

 Pennsylvania to South Dakota; Louisiana to Mexico. 



598. E. heterophylla L. \_P. heterophylla (L.) Small]. 

 Frequent along streams in the crevices of rocks. 

 Illinois and Minnesota to Montana; south to Florida, 



Central America, Peru and Brazil. 



