430 Karl M. Wiegand and Arthur J. Eames 



toothed, lobes ; upper leaves, when dissimilar, unlobed and lanceolate or 

 ovate-lanceolate, rarely oblanceolate or obovate, entire or toothed (see also 

 3d d). 3a. L. canadensis, 



var. latifolia 

 d. Leaves all unlobed, or the basal ones slightly lobed. 

 c. Leaves lanceolate to ovate-lanceolate, entire or rarely toothed, the lower- 

 most ones sometimes slightly lobed. 3b. L. canadensis, 



var. integrifolia 

 e. Leaves oblanceolate or obovate, usually toothed. 3c. L. canadensis, 



var. obovata 

 b. Flowers pale blue; achenes narrowed above, but not slender-beaked, 3-nerved 

 on each face. 4. L. spicata 



1. L. scariola L. Prickly Lettuce. 



Gravelly waste places, mostly in calcareous soils ; rare. Aug. 



Library slope, C. U. campus ; bank of Fall Creek between Lake St. and Cayuga 

 St., Ithaca; roadside, Cayuga Heights; Kidders. Of recent introduction. 



N. E. to Ohio, southw. to Ga., Tenn., and Mo., but mostly westw. Adventive from 

 Eu. 



la. L. scariola L., var. integrata Gren. & Godr. 



In situations similar to the preceding ; common. Aug. 



Widely distributed across the northern part of the continent. Naturalized from 

 Eu. 



2. L. hirsuta Muhl. 



Dry open banks, in gravelly or sandy, somewhat acid, soils ; rare. Aug. 



A few plants along the Boulevard Road, between the s. w. corner of Cayuga 

 Lake and Glenwood, 1915 (A. J. E. & L. H. MacDanicIs), found again in 1920. 



Que. to Ala. and Tex., chiefly e. of the Allegheny Mts., especially on the Coastal 

 Plain. 



3. L. canadensis L. Wild Lettuce. 



Dry gravelly banks by roadsides, and in similar situations, with little reference to 

 the lime content of the soil ; common. July-Sept. 



Absent or rare in the heavier soils of the basin. 



N. S. to B. C, southw. to Ga., Ala., La., Ark., and Colo., including the Atlantic 

 Coastal Plain. 



The form with the leaf bases not sagittate but tapering (forma angustipcs Wie- 

 gand) occurs at Sheldrake, which is the type locality of this form. 



3a. L. canadensis L., var. latifolia O. Kuntze. (See Rhodora 22:9. 1920.) 



In situations similar to the preceding : frequent. 



Enfield Glen ; near Glenwood ; Renwick slope ; shore of Cayuga Lake, from Ren- 

 wick to Myers ; and elsewhere. 



P. E. I. to Wis., southw. to Fla. and Okla. 



The form without the sagittate leaf-base is forma exauriculata Wiegand: Enfield 

 Glen ; McKinneys ; Myers Point. 



3b. L. canadensis L., var. integrifolia (Bigel.) Gray. 



In situations similar to the preceding; frequent. 



Six Mile Creek; Cascadilla Creek; Fall Creek; Ithaca flats; Cayuga Heights; 

 and elsewhere. 



P. E. I. to Wis., southw. to Ga., 111., Okla., and Nebr. 



The form with the leaf base not auricled is forma angustaia Wiegand: Six Mile 

 Creek; L. V. R. R. yards, Ithaca. 



