136 MICHIGAN ACADEMY OF SCIENCE. 



*2233. C. lanceolatus I^. Common or Bull Thistle. Roadsides and fields. Common. 

 Th. 



*2234. C. muticus (Mich.) Pers. Swamp Thistle. Cnicus miiticiis Pursh. Swamps, 

 low land. Frequent. Th. 



2235. C. odoratus (Muhl.) Porter. C. pumihis Nutt. S. W. Mich., Wright's Cat.; 

 Macomb Co.. Dr. Cooley; Baldwin, W. J. B. ; Cheboygan Co., B. & K. 



2236. C. Pitcheri (Torr.) Porter. Pitchers Thistle. Cnicus PiMieri Torr. Shores 

 of the Great Lakes; sand dunes. 



2237. C. spinosissimus Walt. Yellow Thistle. Cnicus Jwrridus Pursh. N. shore 

 Lake Superior. Agassiz; Grand Detour, T. C. Porter. 



2238. C. undulatus Nult. Wavy-leaved Thistle. Cnicus undulatus A. Gray. Islands 

 of Lakes Huron and Michigan, A. Gray; Drummond's I., Winch. Cat. N. & U. P. 



MARIANA Hill. Silybum Gaertn. 



*2239. M. Mariana (L.) Hill. Milk Thistle. Sihjhum Mariamnn Gaertn. Occasional. 



ONOPORDON L. 



2240. 0. Acanthium L. Cotton or Scotch Thistle. Grand Rapids; Detroit, O. A. 

 Farwell. Rare. 



CENTAUREA L. 



2241. C. Cyanus L. Blue-bottle. Escaped from gardens. 



2242. C. nigra L. Black Knapweed. Centaury. Bay City, G. M. Bradford. 



ECHINOPSIS. 



2243. E. sphaerocephalus L. Well established at Three Rivers, C. F. Wheeler. 

 Grand Rapids, H. C. Skeels. Introduced from Europe as a plant for bees. 



