BEPORT OF THE BOTANIST. 87 



their rind, are occasionally used as a substitute for asparagus. In 

 Japan it is cultivated under the name of gobo, the root, growing to 3 

 or 4 inches in diameter and often 2 feet long, being used much as we 

 use salsify. , 



Plate VII, Fig. 1, a branch of the small variety; Fig. 2, a single 

 flower magnified; Fig. 3, a portion of the large-headed variety — major. 



Xanthium Canadense (clot-bur, cockle-bur). 



A coarse branching annual plant of the order Composited, usually 

 1 to 3 feet high, with alternate, rough leaves from 3 to 6 inches long 

 and about as wide, somewhat lobed and coarsely toothed, strongly 

 three ribbed, somewhat heart-shaped at the base, and on long stalks. 

 The flower-heads are in small axillary and terminal clusters of 2 

 kinds, male and female, the male heads on a short spike at the 

 summit and the female in clusters of 2 or 3 at the base of the male 

 spike. The male or staminate flowers are in roundish heads, with a 

 thin scaly involucre. After shedding the pollen these heads soon 

 drop off and disappear, and the female heads enlarge, and become 

 thick, hard, oblong burs about an inch long, beset with stiff hooked 

 prickles. At the apex of the bur there are two hard and sharp or 

 hooked beaks, and within are two cells, each containing a single 

 seed. Those who are accustomed to look at the aster and the sunflower 

 as representatives of the order Comjjosifce, will not at first recognize 

 this plant as a member of that family because of the separation of the 

 male and female flowers, but a close examination will reveal its true 

 position. 



This plant is most abundant on low pasture and stubble land and 

 along streams, though often growing rankly in waste places on up- 

 land. • It is seldom a troublesome weed in crops, but its burs are a great 

 annoyance in the fleeces of sheep. Seeding to clover and meadow 

 grass and mowing several times the first season is recommended for 

 its destruction. 



We have figured this species {X. Canadense), believing that it is 

 the one which is troublesome in corn fields and roadsides in the West- 

 ern States, where it is probably native, but perhaps introduced from 

 the South through travel and commercial intercourse. The species 

 which occurs in the Eastern States is probably Xanthium struma- 

 rium, which is supposed to be a native of Europe and India. It is 

 smaller in size, with smaller burs, more slender and smoother prickles. 



Dr. Gattinger, of Nashville, Tenn., states that some twenty-two 

 years ago he fed his horse quite a quantity of the Xanthinm Cana- 

 dense in its flowering season. It possesses an aromatic smell, and his 

 horse liked it. It did not have any noxious effects upon him, although 

 he has since heard a farmer say that it was poisonous to stock, which, 

 however, he does not believe. 



Plate VIII, Fig. 1, a branch, showing the spikes of male flower- 

 heads, with the female clusters below; Fig. 2, three mature* burs. 



Ambrosia artemisicefoUa (rag- weed, bitter- weed, hog- weed, 

 Roman wormwood). 



A common annual weed of the natural order Comjoositce, gener- 

 ally 2 to 3 feet high, rather slender, and much branched. The leaves 

 are from 1 to 4 inches long, mostly alternate and thinnish, pinnat- 

 ifid, or cut into deep narrow lobes, which are again lobed or toothed. 

 The ends of the branches bear the flowers, which are of 2 kinds, 

 male and female. The male flowers are in small heads of 6 to 8 to- 



