ASTERACEAE: CICHORIEAE 195 



1. Sonchus asper (L.) All. Sow-thistle. 



A common weed throughout the state. Central City; Hastings; Hat 

 Creek Basin; Kearney; Lincoln; Nebraska City. 



7. Lactuca. 897. 



Flowers yellow; beaks of the achenes as long as the body. 

 Margins of the leaves, and often also the midribs, spiny. 

 Heads 6-12 flowered, involucre 8-12 mm. high. 



Leaves sinuate-pinnatifid. 1. L. scariola. 



Leaves merely irregularly denticulate. 



1a. L. scariola var. integrata. 



Heads 12-20 flowered, involucre 10-20 mm. high. 2. L. ludoviciana. 



Margins of the leaves not spiny. 3. L. canadensis. 



Flowers blue or violet; achenes beakless or beak shorter than the 



body. 



Achenes flat; involucre 15-20 mm. high. 4. L. pulchella. 



Achenes thicker slightly compressed, involucre 10-12 mm. high. 



Achenes not beaked; leaves not pinnatifid. 5. L. villosa. 



. Achenes short beaked; leaves pinnatifid. 6. L. floridana. 



1. Lactuca scariola L. 

 Red Cloud. 



la. Lactuca scariola integrata Gren. & Godr. 



A. common weed in the eastern part of the state. Minden; Nebraska 



City; Red Cloud; Republican. 



2. Lactuca ludoviciana (Nutt.) DC. Western Wild Lettuce. 

 A common weed all over the state. Banner County; Cherry County; 

 Franklin; Grand Island; Mullen; Nebraska City; Minden; Pishelville; 

 Plummer Ford. 



3. Lactuca canadensis L. Wild Lettuce. 

 A common weed throughout the state. Cherry County; Long Pine; 

 Nebraska City; Pishelville; Plummer Ford; Sioux County; St. Paul. 



4. Lactuca pulchella (Pursh.) DC. Blue Lettuce. 

 Throughout the state. Cherry County; Brown County; Lincoln; 

 Mullen; Nebraska City; Niobrara; Sioux County. 



5. Lactuca villosa Jacq. 

 Crawford; Nebraska City; Saltillo. 



6. Lactuca floridana (L.) Gaertn. 

 Reported from Crete. 



8. Lygodesmia. 899. 



Heads solitary at the ends of the branches, leaves short. 1. L. juncea. 



Heads racemose, leaves elongated linear, the lower 7 cm. or more 



long. 2. L. rostrata. 



1. Lygodesmia juncea (Pursh.) D. Don. 



Common in prairies throughout the state. Anselmo; Cherry County; 

 Freeport; Grand Island; Kearney; Lincoln; Mullen; Minden; Nattick; 

 Sioux County; Valentine. 



2. Lygodesmia rostrata A. Gray. 



Less common than the last. Kennedy; Long Pine; Minden; Valentine. 



