244 IOWA ACADEMY OF SCIENCE Vol. XXVI, 1919 



Specimens examined : 



lozva: Harlan, PaiuiiicI, 1916; Frazer, Hayden and Henderson, 

 1916; Ames, Pammel, 1916; Sioux City, Mrs. Taylor, 1916; Fair- 

 mont, Mrs. Tuttlc, 1918; Burlington, Pammel, 1918; Goldfield, 

 Cratty, 1919; West Bend, Cratty, 1919; Avoca, Pammel, 1919. 



North America : Ohio — Gambier, Pammel, 1918. Illinois — Ur- 

 bana, Trelease, 1916, 2 sheets; Chicago, Pammel, 1887. Minnesota 

 — Black Duck, Mrs. Westley, 1918. Nebraska — Hastings, Pammel, 

 1895. Colorado— GoXdtn, Pammel, 1895, altitude 8,000 feet. Dist. 

 of Col. — Washington, Dewey, 1895. 



3. Lactuca canadensis L. Sp. Plant, 796 (1753). Wild or Tall 

 Lettuce; Wild Opium. 



Glabrous and somewhat glaucous throughout, three to ten feet 

 high, leafy up to the narrow branched panicle. Leaves mostly 

 sinuate-pinnatifid, the upper lanceolate and entire ; stem leaves 

 clasping, the lower sometimes ten to twelve inches long and nar- 

 rowed into a petiole. Flowers yellow, numerous, the heads four 

 to seven lines high. Akenes oval, flat, about as long as the beak, and 

 having a distinct margin and strongly one-nerved on each face. A 

 most variable species, especially in its leaf forms. 



Open places in moist soil from Nova Scotia to the Northwest Ter- 

 ritory and south to Georgia, Louisiana and Colorado. Common 

 throughout Iowa, but not especially troublesome. 



Specimens examined : 



Iowa: Ames, Pammel, 1911, 2 sheets; E. D. McKune, 1916, 2 

 sheets; Burlington, Pammel, 1917; Fairmont, Mrs. Tiittle, 1918; 

 Clear Lake, Cratty, 1918; McGregor, Pammel, 1918; Decorah, God- 

 dard, 1895, 2 sheets; Des Moines, Canrr, 1895; Pammel, 1902; 

 Bakkc, 1912 ; McKune, 1916, 2 sheets ; Keokuk. Rolfs, 1891 ; Ogden, 

 Pammel, 1898; Boone. FJlis, 1914; Armstrong, Cra/h', 1897; Mason 

 City, Pammel, 1902; Fayette, Fink, 1896; Adel, C. F. Clark, 1907; 

 Decatur, Anderson, 1914; Postville, Pammel, 1918; Frazer, Pammel, 

 1916; Salem, Jaqnes; Kelly, Miss Clayton, 1911; Johnson County, 

 Fitcpatrick, 1904 and 1905; Jefferson County, Fitr.patrick, 1900; 

 Winneshiek County, Goddard, 1895; Decatur County, Fitzpatrick, 

 1898; Jackson County. Shimek, 1894; Lee County, Paul Bartsch, 

 1895; Greene. Pammel, 1919; Madison County, Pammel, 1919. 



North America: Illinois — Walnut, P(7>;/;;/r/. 1918. Minnesota — 

 Black Duck, Mrs. Westley, 1918; Anoka. Crafty, 1918; Cass Lake, 

 Pammel, 1914. Missouri — Kansas City, Pammel, 1918; St. Louis, 

 Grecneman, 1916. Wisconsin — Prescott, Miss Edgar, 1915; "Wis- 



