﻿III. 



WILD LETTUCE AS WEED AND COMPASS PLANT 



The prickly lettuce is a plant closely resem- 

 bling the common garden lettuce, especially 

 the narrow leaved Cos varieties. The simi- 



laritv is more striking if we compare them , „ 



r ' ■, n 111 1 Likeness to 



after the flower stalks have begun to appear, cultivated 



There are in fact good grounds for believing lettuce 



that the garden forms were derived from the 



wild lettuce : a view held at one time by Bis- 



chofif, DeCandolle, and other authorities, who 



wrote the Latin name of the garden forms 



Lactuca Scariola var. sativa, instead of L. 



sativa, as adopted by Linnaeus and adhered 



to by most of recent writers. 



The plant is an annual, coming from seed 



each year. Occasionally the seed germinates 



in the fall, the plant making some growth be- 



*A portion of Bulletin No. 52 of the Indiana Experiment Sta- 

 tion, issued November 10, 1894. 



