234 IOWA ACADEMY OF SCIENCES. 



corolla tube ten cue-half lines long, anther with very acute tips, 

 achenium one and one-half lines long, pappus plumose. 



A specimen in the Engelmann Herbarium as well as 

 several in the Gray Herbarium, are ticketed Cirslum canes- 

 cens. 



In the Gray Herbarium is a specimen ticketed Cirslum 

 iindfdafum B, Torrey and Gray. Flora of North America, 

 (2: 456), collected by Mr. Charles A. Geyer, in August, 

 1839, and labeled "Fertile prairies, near Devil's Lake, the 

 only specimen found; please return it to Mr. Nicollet after 

 examination." There is a note by Dr. Gray: "Not 

 improbably our C. iindulatum var. ^." 



Dr. Gray, in his revision of the genus Chiicus for the 

 Synoptical Flora of North America (' : 403) says: 



Var. canescens, Gray, is merely a form with smaller heads, sometimes 

 not over an inch high, leaves varying from ciliately-spinulose dentate 

 to deeply pinnatitid. Cirsium canescens and C. brevifolium, Nutt. Trans. 

 Am. Phil. Soc. 7: 421— Minnesota to Mexico and S. Utah. 



Another specimen is ticketed ''Cirsium hookerianinn sas- 

 katchawan, collected by Bourgeau, in 1858, in Palliser, Brit. 

 N. A. Exp." Another specimen of the Rocky Mountains, 

 by Burt, in 1849; this was referred by Dr. Gray to C. undu- 

 latus in the Syn. Fl. N. A. ( 1 : 403). One specimen each in 

 the Gray and Engelmann Herbarium, is ticked " C. canes- 

 cans, Nutt. Collected by Dr. Hay den on the Upper 

 Platte." This in the Gray Herbarium is placed under the 

 variety canescens by Dr. Gray. Rydberg correctly consid- 

 ered it as distinct, and referred his form to Cardmis plat- 

 tensis spinosior; this specimen is clearly a form of Ryd- 

 berg's C. plat fens is. 



The Fendler specimen, No. 73, collected near Fort 

 Kearney, also belongs here. This species seems to be 

 quite common in the Sand Hill region of Nebraska. This 

 species and the Cuicits Nelson i are closely allied to Cnicus 

 Pitcheri. 



In the Gray Herbarium is a specimen marked ""Cnicus 

 a/tissintus, Willd. var. _/77/■yJf«f/?///^s•, Gray. Sandbars of Mis- 

 souri river. Sioux City, Iowa, Hitchcock," Dr. Sereno 

 Watson having referred our Iowa material to the variety 



