XVII. 1. THE BUTTON BUSH. 349 



that the ovary has, in some of the tribes, one, or rarely two 

 ovaries, in others several. 



In this family there are two genera belonging to Massachu- 

 setts : — 



Button Bush, Cephalanthus, with flowers in a globose head ; 



Partridge Berry, Mitchella, flowers terminal, in twos, on a 

 double ovary. 



In the sub-order, Cinchonece, the third sub-tribe, in the divis- 

 ion of Torrey and Gray, is 



Cephala'nthe.e, — distinguished by its flowers and fruit being 

 sessile and densely aggregated on a globose receptacle, the fruit 

 dry and divisible into two or four parts. 



XYII. 1. BUTTON BUSH. CEPHALA'NTHUS. L. 



American shrubs, with oval or lanceolate, opposite or ternate 

 leaves, short stipules, and flowers crowded on a globular, hairy 

 receptacle, with a calyx tube in the shape of an inverted py- 

 ramid, the border four-toothed, a tubular four-cleft corolla, four 

 stamens, fruit inversely pyramidal, leathery, two- to four-celled, 

 separating from the base to the summit into two to four, closed, 

 one-seeded portions. 



The Button Bush. River Bush. C. occidentalis. L. 



Figured in Barton's Flora, III, Plate 91. 



The button bush is found along the banks of slow streams, 

 forming little islets in muddy ponds, and in other situations in 

 which its roots and the lower part of its stem are immersed in 

 water for a considerable portion of the year. From stout, con- 

 torted roots, often several inches in diameter, and from large, 

 prostrate, root-like trunks, it rises with an erect or sinuous 

 stem, to the height of from four to ten feet. On the recent 

 shoots the bark is of a bright, polished, copper color, or olive 

 green, or reddish bronze, with a few brown dots, and turns 

 gradually to a light brown. Afterwards, it begins to crack, 

 and from brown or purplish turns to a dark granite gray. The 

 bark on the older stems is cracked, rough and gray, and often 



