EUPHORBIACEAE 83 



Leaves all alternate. 

 Flowers not white. 



Inflorescence an elongated spike, not over S mm. thick, leaves 

 linear or subulate. 4. P. incarnata. 



Inflorescence globose, over 8 mm. thick, leaves oblong or linear- 

 oblong. 2. P. viridescens. 

 Flowers white. 



Leaves serrulate, the lower reduced to scales. 3. P. senega. 



Leaves entire, their edges revolute, the lowr not reduced to scales. 



6. P. alba. 



1. Polygala verticillata L. 



On dry prairies over the entire state. Cherry County; Dakota County; 

 Kearney; Lincoln; Minden; Ewing; Polk County; Red Cloud; Wei- 

 gand; Weeping Water. 



2. Polygala viridescens L. 

 Atkinson; Xeligh; Rock County. 



3. Polygala senega L. 

 Xeligh. 



4. Polygala incarnata L. 



Nebraska according to Gray's Manual. 



5. Polygala cruciata L. 



Nebraska according to Gray's ^Manual. 



6. Polygala alba Nutt. 



Common in prairies in the western part of the state. Anselmo; Bel- 

 ro.ont; Box Butte County; Culbertson; Kearney; Newcastle; Phelps 

 County; Sioux County; Valentine. 



8. EUPHORBIACEAE. 



Plants canescent with sellate hairs. 1. Croton. 

 Plants glabrous or pubescent with simple hairs. 



Styles fringed. 2. Acalypha. 



Styles 2-cleft. 3. Euphorbia. 



1. Croton. 586. 



1. Croton texensis (Klotzsch.) Muell. 



Common in prairies in the western part of the tsate. Anselmo; Banner 

 County; Broken Bow; Deuel County; Franklin; Haigler; Holt County; 

 Mullen; Pine Ridge; Sheridan County. 



2. Acalypha. 588. 

 1. Acalypha virginica L. 



Common in woods in the eastern part of the state. Bellevue; Frank- 

 lin; Grand Island; Lincoln; Riverton; Wahoo; Weeping Water. 



3. Euphorbia. 590. 



Leaves all opposite. 

 Leaves inequilateral, with oblique bases. 

 Leaves entire. 



Leaves linear over 1 cm. long. 



